ific.uv.esific.uv.es/~fiorini/forAdam/ATL-COM-PHYS-2016-120.pdfonly ATLAS NOTE ATL-COM-PHYS-2016-120...
Transcript of ific.uv.esific.uv.es/~fiorini/forAdam/ATL-COM-PHYS-2016-120.pdfonly ATLAS NOTE ATL-COM-PHYS-2016-120...
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
ATLAS NOTEATL-COM-PHYS-2016-120
9th May 2016Draft version 0.6
1
Search for Neutral MSSM Higgs Bosons H/A → τhadτhad and2
Z′ → τhadτhad produced in 13 TeV Collisions with the ATLAS3
Detector4
Alvarez Piqueras, Damian a, Beckingham, Matthewb, Blumenschein, Ulrike c, Davey, Will e,5
Drechsler, Eric c, Duschinger, Dirk f, Fiorini, Luca a, Goussiou, Anna g, Gwilliam, Carl h,6
Hamity, Guillermo Nicolas i, Hauswald, Lorenzf, Hyneman, Rachel j, Jabbar, Samina k,7
Koneke, Karsten l, Liu, Hao j, Mader, Wolfgang f, McCarn, Allison j, Moore, Roger k, Mori,8
Tatsuya m, Morinaga, Masahiro m, Neubauer, Mark d, Pakela, Julia j, Pickering, Mark Andrew9n, Pranko, Aliaksandr o, Rompotis, Nikolaosg, Sales De Bruin, Pedro Henrique g, Schwarz,10
Thomas Andrew j, Straessner, Arno f, Tanaka, Junichi m, Vickey, Trevor i, Zhang, Lei l,11
Zinonos, Zinonas c12
aInstituto de Fisica Corpuscular (IFIC), Centro Mixto Universidad de Valencia - CSIC13bUniversity of Warwick, Coventry14
cGeorg-August-Universitat Goettingen, II. Physikalisches Institut15dUniversity of Illinois at Urbana-Champaign16
eUniversity of Bonn17fInstitut fuer Kern- und Teilchenphysik, Technische Universitaet Dresden18
gDepartment of Physics, University of Washington, Seattle19hUniversity of Liverpool20
iDepartment of Physics and Astronomy, University of Sheffield21jUniversity of Michigan, Department of Physics22
kUniversity of Alberta23lAlbert-Ludwigs-Universitaet Freiburg, Fakultaet fuer Mathematik und Physik24
mInternational Center for Elementary Particle Physics and Department of Physics, The University of Tokyo25nUniversity of Oxford26
oLawrence Berkeley National Laboratory and University of California, Berkeley27
Abstract28
We report a search for neutral MSSM Higgs bosons and neutral Z ′ bosons produced in29
proton–proton collisions delivered by the Large Hadron Collider (LHC) at center-of-mass30
energy 13 TeVand recorded by the ATLAS detector. The data correspond to an integrated31
luminosity of 3.21 fb−1. The resonances are assumed to decay to a τ+τ− pair with both τ32
leptons decaying hadronically. The results are interpreted in a range of scenarios.33
© 2016 CERN for the benefit of the ATLAS Collaboration.Reproduction of this article or parts of it is allowed as specified in the CC-BY-3.0 license.34
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
Contents35
0 Notes 436
1 Introduction 537
2 Data Samples and Monte Carlo Simulation 738
2.1 Monte Carlo Event Samples 739
2.2 Data Samples 840
3 Object Reconstruction 841
3.1 Hadronic tau decays 942
3.2 Electrons 943
3.3 Muons 944
3.4 Jets 945
3.5 Missing transverse energy 1046
3.6 Overlap removal 1047
4 Event Selection 1048
4.1 Event cleaning 1049
4.1.1 Data quality 1050
4.1.2 Jet cleaning 1051
4.1.3 Collision cleaning 1052
4.2 Event preselection 1153
4.3 Final Selection 1154
4.3.1 b-tag category 1555
4.3.2 b-veto category 1556
4.3.3 Z ′ → ττ cut and count selection 1557
4.4 Same-Sign Control Region 1658
5 Background Estimation 3159
5.1 Data-driven QCD background estimation 3160
5.1.1 Multi-jet Validation Region 3361
5.2 W (→ τν)+jets background estimation 3662
5.2.1 Simulation of spin effects 3763
5.2.2 Sherpa Shape Reweighting 3764
5.3 Modelling of fake taus in MC backgrounds 3965
5.3.1 W (→ µν)+jets control region 4066
5.3.2 Top control region 4067
5.3.3 Fake Rate Measurements 4168
6 Systematic Uncertainties 4369
6.1 Luminosity 4370
6.2 Detector-related uncertainties 4471
6.3 Uncertainties on data-driven background estimations 4972
6.4 Uncertainty on W reweighting 5073
6.5 Background Cross section uncertainties 5174
6.6 Uncertainties on signal modelling 5275
2
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
6.7 Uncertainties on top modelling 5476
7 Z ′ → ττ Signal models 5477
7.1 Signal estimation using Z/γ∗ → Z ′ reweighting 5478
7.2 Sequential Standard Model 5579
7.3 Modifications to the Sequential Standard Model 5580
7.4 Strong Flavor Model 5681
8 Results 5982
8.1 A/H → ττ search 5983
8.2 Z ′ → ττ search 6484
8.3 Combination of τ τhad and τhadτhad channels for the Z ′ → ττ search 6585
9 Conclusions 7086
Auxiliary material 7787
A Post-fit Distributions for Higgs Search Signal Regions 7788
B Statistical Analysis Fit Results For Separate Categories 8189
C Asymptotic Approximation Checks 8390
D MC Samples 8691
E Signal Samples 9192
E.1 Signal acceptance systematics 9193
E.2 Validation of the bbH fast simulation 9194
E.3 Z/γ∗ → Z ′ reweighting validation 9395
F Mass Reconstruction 9496
F.1 Introduction 9497
F.2 MMC 9598
F.3 mTot 9599
F.4 MOSAIC 97100
F.4.1 The Amplitude Calculation 97101
F.4.2 Tau Lepton Decay Amplitudes 98102
F.4.3 ` mode 99103
F.4.4 1p0n mode 99104
F.4.5 Decay of Vector Meson 100105
F.4.6 Markov Chain Mote Carlo algorithms 101106
G Final Discriminant Studies 103107
G.1 MSSM Higgs search 103108
G.2 Optimisation of the b-tag category definition 104109
G.3 Z ′ → ττ search 104110
H mT(τ1, EmissT
) mismodelling studies 106111
9th May 2016 – 16:38 3
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
H.1 Motivation 106112
H.2 Studies 106113
H.3 Conclusion 109114
0. Notes115
The analysis documented here is a continuation of the effort that is documented in ATL-COM-PHYS-116
2015-659 that resulted in ATLAS-CONF-2015-061. This version is for the 2015 data paper.117
Overview of changes with respect to the EOYE version:118
• selection optimisation (leading tau threshold)119
• event selection split in b-tag/veto categories120
• Z’ signal interpretation using inclusive selection121
• updated fake background estimation122
– measured fake factor for b-tag/veto123
– measured fake rates for top and W+jets separately124
– updated W+jets corrections125
Status: All the main features of the analysis are finalised.126
The main updates of the note are: the selection in Section 4, the background estimations in Section 5,127
the Z ′ → ττ signal description is in Section 7. The main changes in the appendix are the addition of the128
Z ′ → ττ validation studies in Appendix E.3 and the optimisation studies in Appendix G.129
Updates since version 0.5130
• added Z’ interpretations: SFM, L/R, narrow/wide decay width131
• (small) update of additional postfit plots in Appendix A (considering the recent changes in lephad132
and the combined workspaces)133
Updates in version 0.5134
• a bug was fixed in the workspaces, resulting in updated limits, pulls and postfit plots. The impact135
is very small.136
• added pull plots for separate b-tag and b-veto fits in Appendix B.137
• post-fit distributions for the combined τlepτhad+τhadτhad conditional µ = 0 fit have been added in138
Appendix A.139
Updates in version 0.4 (circulated for unblinded Higgs approval)140
• fixed a bug related to JES systematic uncertainties. These are relatively small uncertainties and due141
to this fix there was no visible change in the limit fits.142
• unblinded all signal regions and added observed limits and pulls143
• combination of τlepτhad and τhadτhad results of Z’ search144
9th May 2016 – 16:38 4
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
• added checks of the asymptotic approximation for selected high mass points (Appendix C)145
Updates in version 0.3 (circulated for unblinding approval)146
• a correction of the top fake rates, due to a true tau contamination of the control region, is applied147
• the binning of the fake factor has been improved148
Updates in version 0.2149
• the QCD background estimation is now corrected for contamination of the fail-ID control region150
and Fake factor derived independently for b-tag and b-veto, plots and cutflows updated accordingly151
• expected limit and Asimov pull plots have been added152
• top modelling systematics153
• W (→ τν)+jets reweighting systematics154
• bbH signal acceptance systematics split in btag/veto, ggH systematics updated155
• several CP recommendation updates, including new systematic variations as part of the updated tau156
energy scale recommendation and new JVT SF systematics157
• (editorial) removed “loose BDT requirement” in from Section 3.1 as it is actually not applied158
• CDS comments implemented159
1. Introduction160
The discovery of a scalar particle at the Large Hadron Collider (LHC) [1, 2] has provided important161
insight into the mechanism of electroweak symmetry breaking. Experimental studies of the new particle162
[3–7] demonstrate consistency with the Standard Model (SM) Higgs boson [8–13]. However, it remains163
possible that the discovered particle is part of an extended scalar sector, a scenario that is favoured by a164
number of theoretical arguments [14, 15].165
TheMinimal Supersymmetric StandardModel (MSSM) [16–20] is an extension of the SM,which provides166
a framework addressing naturalness, gauge coupling unification, and the existence of dark matter. The167
Higgs sector of the MSSM contains two Higgs doublets, which results in five physical Higgs bosons after168
electroweak symmetry breaking. The MSSM Higgs sector is CP-conserving at tree level and assuming169
that higher order corrections conserve CP the Higgs bosons are such that two are neutral and CP-even170
(h, H), one is neutral and CP-odd (A), 1 and the remaining two are charged (H±). At tree level, the171
mass of the light scalar Higgs boson, mh, is restricted to be smaller than the Z boson mass, mZ . This172
bound is weakened due to radiative corrections up to a maximum allowed value of mh ∼ 135 GeV. Only173
two additional parameters are needed with respect to the SM at tree level to describe the MSSM Higgs174
sector. These can be chosen to be the mass of the CP-odd Higgs boson, mA, and the ratio of the vacuum175
expectation values of the twoHiggs doublets, tan β. Beyond lowest order, theMSSMHiggs sector depends176
on additional parameters, which are fixed at specific values in various MSSM benchmark scenarios. For177
example, in the mmaxh
scenario the radiative corrections are chosen such that mh is maximised for a given178
1 By convention the lighter CP-even Higgs boson is denoted h, the heavier CP-even Higgs boson is denoted H . The masses ofthe three bosons are denoted in the following as mh , mH and mA for h, H and A, respectively.
9th May 2016 – 16:38 5
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
g
g
h/H/A
(a)
g
g b
b
h/H/A
(b)
g
b
b
h/H/A
(c)
Figure 1: Example Feynman diagrams for (a) gluon fusion and (b) b-associated production in the four-flavour schemeand (c) five-flavour scheme of a neutral MSSM Higgs boson.
tan β and MSUSY [21, 22]. 2 This results for MSUSY = 1 TeV in mh ∼ 130 GeV for large mA and tan β. In179
addition, in the same region the heavy Higgs bosons, H , A and H±, are approximately mass degenerate180
and h has properties very similar to a SM Higgs boson with the same mass. This feature is generic in the181
MSSM Higgs sector: a decoupling limit exists defined by mA mZ in which the heavy Higgs bosons182
have similar masses and the light CP-even Higgs boson in practice becomes identical to a SMHiggs boson183
with the same mass.184
The discovery of a SM-likeHiggs boson, withmass that is nowmeasured to be125.36±0.37 (stat)± 0.18 (syst) GeV185
[24], has prompted the definition of additional MSSM scenarios [23]. Most notably, the mmod+h
and mmod−h
186
scenarios are similar to the mmaxh
scenario, apart from the fact that the choice of radiative corrections is187
such that the maximum light CP-even Higgs boson mass is ∼ 126 GeV. This choice increases the region188
of the parameter space that is compatible with the observed Higgs boson being the lightest CP-even Higgs189
boson of the MSSM with respect to the mmaxh
scenario. There are many other MSSM parameter choices190
beyond these scenarios that are also compatible with the observed SM Higgs boson, for instance, refs.191
[25, 26].192
The couplings of the MSSMHiggs bosons to down-type fermions are enhanced with respect to the SM for193
large tan β values resulting in increased branching fractions to τ leptons and b-quarks, as well as a higher194
cross section for Higgs boson production in association with b-quarks. This has motivated a variety of195
searches in ττ and bb final states at LEP [27], the Tevatron [28–30] and the LHC [31–34].196
Additional heavy Z ′ gauge bosons appear in many models [35–39] and are “one of the best motivated197
extensions of the standard model (SM)” [40]. Z ′ bosons often arise in grand unified theories and198
while they are typically considered to obey lepton universality, this is not necessarily a requirement. In199
particular, somemodels offering an explanation for the highmass of the top-quark, predict that such bosons200
preferentially couple to third-generation fermions [41, 42]. Non-universal Z ′ models can also explain201
the anomalous dimuon production observed at the D0 experiment [43] and the excess in semileptonic202
B-meson decays into τ-leptons observed at the Belle and BaBar experiments [44]. Searches in the ditau203
channel are also sensitive to sgoldstino-like scalars in supersymmetric models [45, 46], hidden sector Z ′204
models [47] and to the anomalous τ-lepton dipole moments and higher order τ-gluon couplings [48].205
2 The supersymmetry scale, MSUSY, is defined here as the geometric average of the mass of the third generation squarksfollowing refs. [21–23].
9th May 2016 – 16:38 6
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Direct searches for high-mass ditau resonances have been performed by the ATLAS [49] and CMS [50]206
collaborations using 5 fb−1 of integrated luminosity at√
s = 7 TeV. Both searches exclude Z ′SSM with207
masses below 1.4 TeV at 95% CL. ATLAS [51] updated the result using 20 fb−1 of integrated luminosity208
at√
s = 8 TeV to exclude Z ′SSM with masses below 1.9 TeV at 95% CL. The Sequential Standard Model209
(SSM) contains a single additional Z ′ boson with the same couplings as the SM Z boson, and while210
not theoretically well motivated, serves as a benchmark. Indirect limits on Z ′ bosons with non-universal211
flavour couplings have been set using measurements from LEP and LEP II [52] and translate to a lower212
bound on the Z ′mass of 1.09 TeV. For comparison, the most stringent limits on Z ′SSM in the dielectron and213
dimuon decay channels combined are 2.90 TeV from ATLAS [53] and 2.96 TeV from CMS [54]. While214
searches in these channels are in general more sensitive than in the ditau channel, they may be evaded by215
models with weak couplings to electrons and muons.216
This note presents the results of a search for a neutral MSSMHiggs boson as well as high-mass resonances217
into two tau leptons using 3.2 fb−1 of proton–proton collision data collected with the ATLAS detector218
[55] in 2015 at a centre-of-mass energy of 13 TeV. Tau leptons can decay into a charged lepton and219
two neutrinos (τlep = τe or τµ), or hadronically (τhad), predominantly into one or three charged pions, a220
neutrino and often additional neutral pions. The τhadτhad decay channel with a branching ratio of BR=42%221
is analysed in this document. Higgs boson production through gluon fusion or in association with b-quarks222
is considered (see figure 1), with the latter mode dominating for high tan β values. The results of the223
search are interpreted in various MSSM scenarios. Limits on the cross section times τ+τ− branching224
fraction of a generic neutral resonance are reported. The impact on the signal acceptance from altering Z ′225
couplings is evaluated and limits are also placed on a particular model that exhibits enhanced couplings226
to tau-leptons. Limits on the various Z ′ models are obtained by performing a counting experiment from227
events that pass a high-mass requirement.228
2. Data Samples and Monte Carlo Simulation229
2.1. Monte Carlo Event Samples230
Monte Carlo samples used by this analysis are produced with the ATLAS simulation infrastructure [56]231
as part of the ATLAS mc15 production campaign. The following samples and generators listed in232
Tables 19–22 of Appendix D have been used.233
Simulated samples that have been used for the following processes: W+jets, Z+jets, tt, single top and234
diboson. The W+jets process is modelled with Sherpa 2.1.1 generator [57], while the Z+jets the235
POWHEG [58] generator was used and the events were subsequently showered with Pythia8 [59, 60]. For236
the tt and single top samples POWHEG was used as well, but the events were showered with Pythia6 [59].237
Diboson samples have been generated and showered with Sherpa. The Z+jets samples are simulated in238
slices with different masses of the off-shell boson mass. In order to avoid the overlap the inclusive samples239
are truncated keeping only events with m? < 120 GeV, where m? denotes the the off-shell boson mass.240
The procedure used is in agreement with the physics modelling group recommendations.241
Two production processes of heavy neutral MSSM Higgs bosons have relevant cross sections for this242
analysis: gluon fusion and b-associated production. Samples of b-associated production events at 11243
different Higgs masses have been generated using the MadGraph5_aMC@NLO 2.1.2 generator [61, 62].244
Gluon fusion samples with the same masses were generated using POWHEG [58]. The generation of245
parton shower, underlying event and hadronisation was performed using Pythia 8.2 [63] for both signal246
9th May 2016 – 16:38 7
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
processes. Due to the fact that MadGraph5_aMC@NLO 2.1.2 generator produces a lot of events with247
negative weights, a fact that has been confirmed by the package developers in the LHC Higgs cross248
sections group, much larger statistics with respect to the gluon-fusion samples have to be generated. For249
this reason the ALTFAST-II simulation has been used to simulate these events. The fast simulation has250
been validated against full simulation for a single mass point and the results of this study are shown in251
Appendix E.252
The contributions of the various Z ′ signal models are estimated by reweighting the leading order Z/γ∗ →253
ττ sample using the TauSpinner algorithm [64], which correctly accounts for spin effects in the tau254
decays.255
The used Z/γ∗ → ττ sample, enriched in high-mass events, is generated with PYTHIA 8.165[60]. The256
A14 tune is used together with the NNPDF2.3LO PDF set[65]. A leading-order generator was chosen so257
that the sample could also be reweighted as Z ′ signal. A detailed description of the reweighting procedure258
is given in Section E.3. Interference of the Z ′ signals with the SM Z/γ∗ is not included. For each signal259
model, 18 mass hypotheses are considered, ranging from 500 to 1000 GeV in steps of 100 GeV and up to260
4000 GeV in steps of 125 GeV.261
Each sample was passed through the full GEANT4 [56, 66] simulation of the ATLAS detector and is262
reconstructed with the same software as used for data. The only exception is the bbH signal samples that263
have used the fast simulation.264
2.2. Data Samples265
The data used for this version of the note corresponds to 3.2 fb−1. Events which the trigger is unable to266
process in time or causing errors in the online reconstruction are redirected to the debug stream. These267
events are taken into account in the analysis to avoid bias in the event selection. The events from the268
debug stream were processed and no event passed the analysis selection criteria.269
Data where the IBL was not fully operational have not been used, since we use b-tagging to define signal270
region categories. Data from the 50ns configuration are not used as well, since they correspond to a small271
fraction of the data without a visible impact in sensitivity.272
3. Object Reconstruction273
The topology of A/H/h → ττ events makes it necessary to reconstruct hadronically decaying τ leptons274
and missing transverse energy EmissT . In order to suppress backgrounds, it is also important to reconstruct275
electrons, muons and jets.276
The pre-recommendation of the Combined performance groups are used in this analysis.277
9th May 2016 – 16:38 8
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
3.1. Hadronic tau decays278
The tau reconstruction [67] is seeded by jets formed by the anti-kt algorithm applied on calibrated topo279
clusters with a distance parameter of R = 0.4. To discriminate the visible decay products of hadronically280
decaying tau leptons τhad-visfrom jets initiated by quarks or gluons, which are much more common at the281
LHC, an identification algorithm based on Boosted Decision Trees is applied to τhad-vis candidate objects.282
Only candidates with pT > 40 GeV and |η | < 2.5 are considered. Requirements on the BDT jet rejection283
are applied at a later stage (see Sec. 4). In the baseline object selection for the analysis presented here284
τhad-vis are required to have one or three charged tracks, an absolute charge of one, a minimum pT of285
20 GeV and to be located in |η | < 2.5 (excluding the crack region 1.37 < |η | < 1.52). Tau candidates286
with one core track that overlap (∆R < 0.4) with an electron candidate (pT > 5GeV) which has a high287
electron ID Likelihood score are rejected. The cut on the Likelihood score is parametrised in η and pT288
such that the tau efficiency is constant at 95% (loose ID) [68].289
3.2. Electrons290
Electron reconstruction begins with tracks in the inner detector that are matched to clustered energy291
deposits in the electromagnetic calorimeter. Electron candidates are required to pass a “loose” likelihood-292
based identification selection point, have pT > 15 GeV and to be in the fiducial volume of the detector,293
|η | < 2.47. The transition region between the barrel and end-cap calorimeters (1.37 < |η | < 1.52) is294
excluded.295
3.3. Muons296
Objects are considered as muon candidates if an inner detector track matches a track reconstructed in the297
muon spectrometer [69]. Muon candidates are required to have pT > 7 GeV and |η | < 2.5. Muons must298
be reconstructed with the muid algorithm, and pass a gradient isolation criterion that is expected to be299
90(99)% efficient for muons of pT 25 (60) GeV.300
3.4. Jets301
Jets are reconstructed using the anti-kt algorithm [70, 71] with a distance parameter R = 0.4 applied to302
topological clusters of calorimeter cells. The jet energy is calibrated using the electromagnetic scaling303
scheme (EM). In order to identify the jets initiated by b-quarks, theMV2c20 algorithm is used [72], which304
uses variables constructed by the IP2D, IP3D, SV1 and JetFitter algorithms into amultivariate discriminant305
“w” with values between minus and plus one. A working point that corresponds to an average efficiency306
of 70% for b-jets in tt events is chosen (corresponding to a weight wMV2C20 > −0.0436). Tagging307
and mis-tagging efficiency scale factors relate efficiencies as determined in various data samples to their308
counterparts in simulation. They are used in all simulated events, after having applied the b-tagging309
algorithm to the jets. The b-tagged jets are required to pass the pT > 20 GeV and |η | < 2.4 requirements.310
Jets with pT < 50 GeV and |η | < 2.4 are required as well to have |JVT| > 0.64. JVT is the is the output of311
the jet vertex tagger algorithm, used to identify and select jets originating from the hard-scatter interaction312
through the use of tracking and vertexing information [73].313
9th May 2016 – 16:38 9
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
3.5. Missing transverse energy314
Themissing transversemomentum (EmissT ) definition used in this analysis is an object-based definition [74].315
It is computed using fully calibrated and reconstructed physics objects. The SoftTerm of the EmissT is316
computed using the TrackSoftTerm (TST) algorithm as it is the default for Run II analysis.317
3.6. Overlap removal318
Geometric overlap between objects passing the above selection creates ambiguity in the identity of the ob-319
jects. Thus an overlap removal is applied between the objects whose ∆R (defined as: ∆R ≡√∆φ2 + ∆η2)320
is less than a certain threshold. When two objects do not matching this requirement, the one that is kept321
is given by following this order: muons, electron, taus and jets.322
323
The ∆R threshold is not the same for the different combinations and hence, is defined below:324
• Jets within a ∆R = 0.2 cone of the leading pT τhad are excluded.325
• Jets within a ∆R = 0.4 cone of an electron or muon are excluded.326
• τhad within a ∆R = 0.2 cone of electrons or muons are excluded.327
• Electrons within a ∆R = 0.2 cone of muons are excluded.328
4. Event Selection329
4.1. Event cleaning330
4.1.1. Data quality331
Only data eventswithin luminosity blocks thatwere recordedwhile all detector subsystemswhere operating332
on good conditions are considered. The luminosity blocks are filtered using the file333
data15_13TeV.periodAllYear_DetStatus-v73-pro19-08_DQDefects-00-01-02_PHYS_StandardGRL_All_Good_25ns.xml.334
4.1.2. Jet cleaning335
A suppression of jets not associated to real energy deposits, among others due to hardware problems,336
beam conditions and cosmic showers, is performed at the “LooseBad” working point of the ATLAS jet337
cleaning tool. Events containing bad jets are discarded.338
4.1.3. Collision cleaning339
Only events that contain at least one primary vertex with at least two associated tracks are analysed.340
9th May 2016 – 16:38 10
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
4.2. Event preselection341
Events are required to be accepted by the single-tau trigger HLT_tau80_medium1_tracktwo_L1TAU60.342
The leading tau candidate must be matched to the trigger with an angular distance of R = 0.2. A cut on343
pT is applied to the leading tau candidate at 110 GeV and to the subleading tau candidate at 55 GeV.344
Furthermore the leading tau candidate has to pass the “medium” jet BDT rejection, whereas the sublead-345
ing tau candidate is required to pass the “loose” jet BDT discrimination. Leading and subleading tau346
candidates must have a back-to-back topology in the transverse plane, i.e. ∆φ(τ0, τ1) > 2.7, and have347
opposite electric charge. The selection criteria are summarised below:348
349
1. Preselection: At least 2 τhad with pT > 100 GeV and 45 GeV and veto of any electron or muon350
passing loose identification.351
2. PassHLT_tau80_medium1_tracktwo_L1TAU60 single-tau trigger and leading tau candidatematches352
to the trigger.353
3. Leading tau pass the medium jet BDT discrimination.354
4. Leading tau pT > 110 GeV.355
5. subleading tau candidate is required to pass the “loose” jet BDT discrimination.356
6. Subleading tau pT > 55 GeV.357
7. ∆φ(τ0, τ1) > 2.7.358
8. τ1 and τ2 have opposite charge.359
4.3. Final Selection360
After the event preselection different signal regions are defined to provide best separation from signal361
to background. Two orthogonal categories favouring MSSM Higgs from gluon fusion or b-associated362
production are utilized, in the following referred to as the b-veto and b-tag categories, respectively. For the363
search for heavy Z ′ bosons no further cuts on physics objects are applied, rather a cut and count analysis364
is performed.365
Table 1 summarises the opposite sign signal region and same sign control region expected electroweak,366
multijet and top backgrounds as well as data events after the different stages in the cutflow for the b-veto367
and b-tag categories. Table 2 summarises the expected gluon fusion signal sample yields for cross sections368
of 1 pb in the opposite sign b-veto signal region. Table 3 summarises the expected b-associated production369
signal sample yields for cross sections of 1 pb in the opposite sign b-tag signal region.370
9th May 2016 – 16:38 11
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Cut
Data
QCD
stat.
Ztautau
stat.
Wtaun
ustat.
Top
stat.
Others
stat.
Preselectio
n24
0015
4-
-17
974.72
177.75
6606
7.83
677.08
7369
1.51
249.53
1617
0.66
387.53
Trigger&
τID
lead
2367
95-
-14
07.37
44.36
3168
.64
67.25
2955
.93
19.29
343.93
10.75
Leadτ
p T10
6016
--
641.75
29.13
1208
.45
32.04
775.45
9.34
86.26
3.75
Subleadτ
p T71
177
--
509.09
25.56
902.61
28.77
548.84
7.86
61.07
3.41
∆φ
5002
3-
-26
8.02
16.07
503.92
25.08
214.22
4.92
30.28
2.60
Expected
eventy
ieldsfor
SMbackgrou
ndsa
ndob
served
eventsthroug
htheeventselectio
ncommon
tobo
thb-tagand
b-veto
catego
ries
b-veto
4827
0-
-26
0.60
15.77
489.12
25.01
63.66
2.58
28.20
2.37
subleadτID
1034
759.93
7.41
105.56
1.95
47.00
2.24
8.98
0.64
4.54
0.40
Opp
osite
Sign
628
394.35
5.39
100.80
1.89
38.48
1.97
3.98
0.48
4.03
0.38
SameSign
406
366.52
5.10
3.55
0.42
7.51
0.99
0.48
0.05
0.43
0.10
b-tag
1753
--
7.18
2.95
14.39
1.23
149.61
4.15
2.09
1.11
subleadτID
4635
.47
1.87
1.49
0.21
1.17
0.13
23.41
1.02
0.06
0.02
Opp
osite
Sign
2317
.21
1.35
1.33
0.19
0.92
0.12
11.45
0.83
0.05
0.01
SameSign
2316
.58
1.27
0.12
0.06
0.21
0.04
1.14
0.13
0.01
0.00
Table1:
Expected
eventy
ieldsfor
SMbackgroundsa
ndobserved
eventsin
theeventselectio
n.Th
etopsectionof
thetableshow
sthe
eventselectio
ncommon
toboth
categorie
s.Th
esecond
sectionshow
sthe
continuedeventselectio
nin
the
b-veto
category
andthesplit
betweenoppositesign
andsamesign
charge
product
ofthetwotauparticles.Th
ethird
sectionshow
stheeventselectio
nin
the
b-tagcategory
andthesplit
betweenopposite
sign
andsamesign
charge
producto
fthetwotauparticles.A
llnumberscorrespond
toan
integrated
luminosity
of3.21
fb−
1 .
9th May 2016 – 16:38 12
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Cut
ggH30
0W2
stat.
ggH35
0W3
stat.
ggH40
0W5
stat.
ggH50
0W5
stat.
ggH60
0W10
stat.
Preselectio
n39
6.72
3.80
447.59
4.04
491.31
4.26
533.42
4.42
563.12
5.06
Trigger&
τID
lead
178.91
2.58
229.94
2.90
265.98
3.11
301.39
3.25
328.52
3.77
Leadτ
p T12
2.48
2.12
183.11
2.57
228.93
2.87
278.87
3.12
312.92
3.67
Subleadτ
p T10
7.23
1.98
161.89
2.42
208.14
2.73
257.96
2.99
293.52
3.55
∆φ
85.70
1.78
139.07
2.24
184.17
2.57
229.61
2.83
264.11
3.37
b-veto
84.36
1.77
136.94
2.22
182.14
2.56
226.10
2.81
259.60
3.34
subleadτID
64.29
1.54
110.20
2.00
147.09
2.30
187.07
2.55
215.04
3.04
Opp
osite
Sign
63.55
1.53
108.40
1.98
145.26
2.29
184.39
2.53
211.70
3.02
Cut
ggH70
0W20
stat.
ggH80
0W20
stat.
ggH10
00W30
stat.
ggH12
00W40
stat.
Preselectio
n56
5.83
5.07
572.12
5.07
561.37
4.99
542.38
4.91
Trigger&
τID
lead
323.69
3.72
327.61
3.72
320.66
3.65
303.61
3.55
Leadτ
p T31
2.40
3.65
318.79
3.66
315.80
3.62
300.55
3.53
Subleadτ
p T29
6.63
3.55
304.06
3.57
301.48
3.54
287.35
3.45
∆φ
264.46
3.35
273.83
3.39
272.39
3.36
259.59
3.28
b-veto
260.14
3.33
267.54
3.35
265.86
3.32
252.26
3.24
subleadτID
216.72
3.04
222.60
3.06
221.05
3.03
209.47
2.95
Opp
osite
Sign
212.17
3.00
218.63
3.03
216.03
2.99
203.10
2.90
Table2:Ex
pected
eventyieldsfor
gluonfusion
signalsamples
intheoppositesign
signalregion
forthe
b-vetocategory
foranintegrated
luminosity
of3.21
fb−
1 .Allcrosss
ectio
nsaresetto1pb.
9th May 2016 – 16:38 13
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Cut
bbH30
0stat.
bbH35
0stat.
bbH40
0stat.
bbH50
0stat.
bbH60
0stat.
Preselectio
n41
4.20
4.25
466.99
4.51
498.00
3.99
544.37
4.88
553.82
5.49
Trigger&
τID
lead
204.06
2.97
246.84
3.28
277.76
2.94
312.98
3.62
323.29
4.09
Leadτ
p T14
0.05
2.43
198.37
2.89
238.09
2.70
290.78
3.47
308.30
3.98
Subleadτ
p T12
1.07
2.27
176.53
2.72
214.39
2.56
268.70
3.33
289.94
3.85
∆φ
96.30
2.06
143.78
2.50
174.99
2.36
225.42
3.08
247.64
3.58
b-tag
27.26
1.04
46.21
1.31
56.56
1.28
77.26
1.74
87.43
2.07
subleadτID
21.53
0.92
37.03
1.17
44.90
1.15
63.67
1.58
72.59
1.89
Opp
osite
Sign
21.23
0.91
36.51
1.16
44.33
1.14
62.51
1.57
71.59
1.87
Cut
bbH70
0stat.
bbH80
0stat.
bbH10
00stat.
bbH12
00stat.
Preselectio
n56
1.02
5.55
565.52
5.56
548.54
4.92
519.67
5.23
Trigger&
τID
lead
334.64
4.13
338.21
4.12
321.14
3.62
294.02
3.83
Leadτ
p T32
3.58
4.05
331.22
4.07
316.60
3.59
291.91
3.81
Subleadτ
p T30
5.89
3.93
314.34
3.95
301.36
3.50
279.50
3.70
∆φ
261.48
3.66
271.91
3.69
260.61
3.26
241.46
3.45
b-tag
96.54
2.17
105.52
2.22
106.16
2.02
99.32
2.16
subleadτID
81.22
1.98
88.30
2.03
89.12
1.85
82.75
1.98
Opp
osite
Sign
79.54
1.96
86.75
2.02
87.09
1.82
80.21
1.96
Table3:
Expected
eventy
ieldsforb
-associatedproductio
nsignalsamples
intheoppositesign
signalregion
forthe
b-tagcategory
fora
nintegrated
luminosity
of3.21
fb−
1 .Allcrosss
ectio
nsaresetto1pb.
9th May 2016 – 16:38 14
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
4.3.1. b-tag category371
This category is dedicated to the search of MSSM Higgs produced in association with b-quarks. It is372
defined by requiring the presence in the event of at least 1 jet with pT> 20GeV tagged as a b-jet according373
to the identification criteria in Section 3.4. The main backgrounds in this category are the multijet and top374
production processes. Variable distributions after the full selection without the ∆φ(τ1, τ2) requirement, as375
well as after the complete selection are shown in Fig. 2-5. Signal selection efficiencies for selected mass376
points are listed in Table 4.377
Mass Hypothesis [GeV] 200 300 600 1000 1200gluon fusion 0.00 0.07 0.27 0.38 0.40b-associated prod. 0.08 1.56 5.29 6.48 5.93
Table 4: Signal selection efficiency in percent for the b-tag category.
4.3.2. b-veto category378
This category is complementary to the b-tag category and is devoted prevalently to the selection of MSSM379
Higgs bosons produced via the gluon fusion mechanism. Events with no jets with pT> 20GeV tagged as380
a b-jets are selected in this category. The main background processes are the multijet and the Z-boson381
production. Variable distributions after after the complete selection are shown in Fig. 6-7. Signal selection382
efficiencies for selected mass points are listed in Table 5.
Mass Hypothesis [GeV] 200 300 600 1000 1200gluon fusion 0.13 4.70 15.62 16.01 14.98b-associated prod. 0.15 4.01 9.71 9.40 8.50
Table 5: Signal selection efficiency in percent for the b-veto category.383
4.3.3. Z ′ → ττ cut and count selection384
The selection used to define the Z ′ → ττ signal region is based on the total transversemass mtotT . This mass385
definition has been proven numerous times to yield best background rejection, while keeping the signal386
efficiency high[49, 51]. A mass-dependent lower threshold on mtotT is applied, which defines the Z ′ → ττ387
signal region. A study justifying the choice of the specific lower thresholds is described in Section G.3.388
The thresholds are summarised in Table 6. It is ensured, that there is at least one expected background389
event in the final mass window. The main background processes are the irreducible Z/γ∗ → ττ and the390
multijet backgrounds. The key distribution of the total transverse mass including signal hypotheses for 3391
different mZ′ are shown in Fig. 8.392
Mass Point [GeV] 500 – 700 800 900 1000 1250 1500 – 2500mtot
T [GeV] >400 >450 >500 >550 >650 >750
Table 6: Lower thresholds on mtotT used to define Z ′ → ττ signal regions.
9th May 2016 – 16:38 15
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
4.4. Same-Sign Control Region393
The selection criteria used in this search require that the two tau candidates have opposite charge. This394
requirement enhances the purity of the event selection and at the same time offers the opportunity to define395
a control region composed by the events passing the same selection criteria of the signal region, but where396
the charge requirement of the taus is reverted. Figs 9-10 show the variable distributions of the events of397
the same-sign control region of the b-tag category after removing the ∆φ(τ1, τ2) requirement, which is398
composed primarily by events with fake taus: multi-jet and W (→ τν)+jets backgrounds. The variable399
distributions of the events of the same-sign control region of the b-tag category after full event selection400
are shown in Figs 11-12. Figs 13-14 show the variable distributions of the events of the same-sign control401
region of the b-veto category. Figure 15 shows the mtotT distribution with several signal hypotheses for 3402
different mZ′.403
9th May 2016 – 16:38 16
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV] 0τT
p
Eve
nts/
50
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV] 0τT
p100 150 200 250 300 350 400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]0τη
Eve
nts/
0.5
GeV
2
4
6
8
10
12
14
16
18 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]0τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(b)
[GeV] 1τT
p
Eve
nts/
42
GeV
1−10
1
10
210
310
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV] 1τT
p50 100 150 200 250 300D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(c)
[GeV]1τη
Eve
nts/
0.5
GeV
2
4
6
8
10
12
14
16
18 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(d)
[GeV]missTE
Eve
nts/
33
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]missTE
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TsumE
Eve
nts/
100
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]TsumE0 200 400 600 800 1000 1200D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(f)
Figure 2: Variable distributions in the b-tag category after complete selection criteria without the ∆φ(τ1, τ2)requirement: (a) Leading τhad pT, (b) Leading τhad η, (c) Sub-leading τhad pT, (d) Sub-leading τhad η, (e)Emiss
T , (f)Scalar sum of the ET of the objects used in the Emiss
T calculation, ΣET. The distributions correspond to an integratedluminosity of 1 fb−1 and the signal is normalised to 1 pb−1 for illustration purpose.
9th May 2016 – 16:38 17
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
>20 GeV)T
p (bjetN
Eve
nts/
1
1−10
1
10
210
310
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
>20 GeV)T
p (bjetN0 1 2 3 4 5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]jet0
Tp
Eve
nts/
83
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]jet0
Tp
0 50 100 150 200 250 300 350 400 450 500Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,0τ (Tm
Eve
nts/
75
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,0τ (Tm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
) [GeV]missTE,1τ (Tm
Eve
nts/
40
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
ττmvis
Eve
nts/
GeV
3−10
2−10
1−10
1
10=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
ττmvis0 200 400 600 800 1000 1200D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TotTm
Eve
nts/
GeV
3−10
2−10
1−10
1
10=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(f)
Figure 3: Variable distributions in the b-tag category after the complete selection criteria without the ∆φ(τ1, τ2)requirement: (a) Nb−jet, (b) Leading jet pT, (c) mT(τ0, Emiss
T ), (d) mT(τ1, EmissT ), (e) mvis(f) mtot
T . The distributionscorrespond to an integrated luminosity of 1 fb−1 and the signal is normalised to 1 pb−1 for illustration purpose.
9th May 2016 – 16:38 18
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV] 0τT
p
Eve
nts/
50
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV] 0τT
p100 150 200 250 300 350 400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]0τη
Eve
nts/
0.5
GeV
1
2
3
4
5
6
7
8 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]0τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(b)
[GeV] 1τT
p
Eve
nts/
42
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV] 1τT
p50 100 150 200 250 300D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(c)
[GeV]1τη
Eve
nts/
0.5
GeV
1
2
3
4
5
6
7
8=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(d)
[GeV]missTE
Eve
nts/
33
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]missTE
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TsumE
Eve
nts/
100
GeV
1−10
1
10
210
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]TsumE0 200 400 600 800 1000 1200D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(f)
Figure 4: Variable distributions in the b-tag category after complete selection criteria: (a) Leading τhad pT, (b)Leading τhad η, (c) Sub-leading τhad pT, (d) Sub-leading τhad η, (e)Emiss
T , (f) Scalar sum of the ET of the objects usedin the Emiss
T calculation, ΣET. The distributions correspond to an integrated luminosity of 1 fb−1 and the signal isnormalised to 1 pb−1 for illustration purpose.
9th May 2016 – 16:38 19
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
>20 GeV)T
p (bjetN
Eve
nts/
1
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
>20 GeV)T
p (bjetN0 1 2 3 4 5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]jet0
Tp
Eve
nts/
83
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]jet0
Tp
0 50 100 150 200 250 300 350 400 450 500Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,0τ (Tm
Eve
nts/
75
GeV
1−10
1
10
210
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,0τ (Tm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
) [GeV]missTE,1τ (Tm
Eve
nts/
40
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
ττmvis
Eve
nts/
GeV
3−10
2−10
1−10
1
10 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
ττmvis0 200 400 600 800 1000 1200D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TotTm
Eve
nts/
GeV
3−10
2−10
1−10
1
10 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(f)
Figure 5: Variable distributions in the b-tag category after the complete selection criteria: (a) Nb−jet, (b) Leadingjet pT, (c) mT(τ0, Emiss
T ), (d) mT(τ1, EmissT ), (e) mvis(f) mtot
T . The distributions correspond to an integrated luminosityof 1 fb−1 and the signal is normalised to 1 pb−1 for illustration purpose.
9th May 2016 – 16:38 20
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV] 0τT
p
Eve
nts/
15
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV] 0τT
p100 150 200 250 300 350 400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]0τη
Eve
nts/
0.5
GeV
20
40
60
80
100
120
140=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]0τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(b)
[GeV] 1τT
p
Eve
nts/
22
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV] 1τT
p50 100 150 200 250 300 350 400 450D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(c)
[GeV]1τη
Eve
nts/
0.5
GeV
20
40
60
80
100
120
140=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(d)
[GeV]missTE
Eve
nts/
20
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]missTE
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TsumE
Eve
nts/
50
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]TsumE0 200 400 600 800 100012001400160018002000D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(f)
Figure 6: Variable distributions in the b-veto category after complete selection criteria: (a) Leading τhad pT, (b)Leading τhad η, (c) Sub-leading τhad pT, (d) Sub-leading τhad η, (e)Emiss
T , (f) Scalar sum of the ET of the objects usedin the Emiss
T calculation, ΣET. The signal is normalised to 1 pb−1 for illustration purpose.
9th May 2016 – 16:38 21
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
>20 GeV)T
p (bjetN
Eve
nts/
1
1−10
1
10
210
310
410=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
>20 GeV)T
p (bjetN0 1 2 3 4 5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]jet0
Tp
Eve
nts/
25
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]jet0
Tp
0 50 100 150 200 250 300 350 400 450 500Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,0τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,0τ (Tm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
ττmvis
Eve
nts/
50
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
ττmvis0 200 400 600 800 1000 1200 1400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TotTm
Eve
nts/
GeV
3−10
2−10
1−10
1
10
210=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(f)
Figure 7: Variable distributions in the b-veto category after the complete selection criteria: (a) Nb−jet, (b) Leading jetpT, (c) mT(τ0, Emiss
T ), (d) mT(τ1, EmissT ), (e) mvis(f) mtot
T . The signal is normalised to 1 pb−1 for illustration purpose.
9th May 2016 – 16:38 22
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
1
10
210
310
410
510
610
710
eve
nts
Dataττ→*γZ/
QCDντ→W
TopOthers
ττ→(0.500TeV)SSMZ’ττ→(1.000TeV)SSMZ’ττ→(1.500TeV)SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫
InternalATLAS Dataττ→*γZ/
QCDντ→W
TopOthers
ττ→(0.500TeV)SSMZ’ττ→(1.000TeV)SSMZ’ττ→(1.500TeV)SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫
InternalATLAS Dataττ→*γZ/
QCDντ→W
TopOthers
ττ→(0.500TeV)SSMZ’ττ→(1.000TeV)SSMZ’ττ→(1.500TeV)SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫
InternalATLAS Dataττ→*γZ/
QCDντ→W
TopOthers
ττ→(0.500TeV)SSMZ’ττ→(1.000TeV)SSMZ’ττ→(1.500TeV)SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫
InternalATLAS
0.6
0.8
1
1.2
1.4
[GeV]totTm
200 300 400 500
Da
ta/M
C
stat. syst.stat. syst.stat. syst.stat. syst.
Figure 8: mtotT distribution in the inclusive category after the complete selection criteria including exemplary Z ′
signals for mZ′ of 0.5, 1.0 and 1.5 TeV stacked on top of the SM background. The x-axis is in logarithmic scale andbins have been sized equally in that scale. The last bin includes the overflow bin. The distribution correspond to anintegrated luminosity of 1 fb−1.
9th May 2016 – 16:38 23
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV] 0τT
p
Eve
nts/
50
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV] 0τT
p100 150 200 250 300 350 400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]0τη
Eve
nts/
0.5
GeV
2
4
6
8
10
12 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]0τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(b)
[GeV] 1τT
p
Eve
nts/
42
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV] 1τT
p50 100 150 200 250 300D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(c)
[GeV]1τη
Eve
nts/
0.5
GeV
2
4
6
8
10=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(d)
[GeV]missTE
Eve
nts/
33
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]missTE
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TsumE
Eve
nts/
100
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]TsumE0 200 400 600 800 1000 1200D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(f)
Figure 9: Variable distributions in the same-sign control region of the b-tag category without the ∆φ(τ1, τ2)requirement. The integrated luminosity corresponds to 3.21 fb−1. The signal is normalised to 1 pb−1 for illustrationpurpose: (a) Leading τhad pT, (b) Leading τhad η, (c) Sub-leading τhad pT, (d) Sub-leading τhad η, (e)Emiss
T , (f) ΣET.
9th May 2016 – 16:38 24
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
>20 GeV)T
p (bjetN
Eve
nts/
1
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
>20 GeV)T
p (bjetN0 1 2 3 4 5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]jet0
Tp
Eve
nts/
83
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]jet0
Tp
0 50 100 150 200 250 300 350 400 450 500Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,0τ (Tm
Eve
nts/
75
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
) [GeV]missTE,0τ (Tm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
) [GeV]missTE,1τ (Tm
Eve
nts/
40
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
ττmvis
Eve
nts/
GeV
3−10
2−10
1−10
1
10 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
ττmvis0 200 400 600 800 1000 1200D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TotTm
Eve
nts/
GeV
3−10
2−10
1−10
1
10=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]TotTm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(f)
Figure 10: Variable distributions in the same-sign control region of the b-tag category without the ∆φ(τ1, τ2)requirement. The integrated luminosity corresponds to 3.21 fb−1. The signal is normalised to 1 pb−1 for illustrationpurpose: (a) Nb−jet, (b) Leading jet pT, (c) mT(τ0, Emiss
T ), (d) mT(τ1, EmissT ), (e) mvis, (f) mtot
T .
9th May 2016 – 16:38 25
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV] 0τT
p
Eve
nts/
50
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV] 0τT
p100 150 200 250 300 350 400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]0τη
Eve
nts/
0.5
GeV
1
2
3
4
5
6
7=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]0τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(b)
[GeV] 1τT
p
Eve
nts/
42
GeV
1−10
1
10
210
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV] 1τT
p50 100 150 200 250 300D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(c)
[GeV]1τη
Eve
nts/
0.5
GeV
1
2
3
4
5
6
7=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(d)
[GeV]missTE
Eve
nts/
33
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]missTE
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TsumE
Eve
nts/
100
GeV
1−10
1
10
210
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]TsumE0 200 400 600 800 1000 1200D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(f)
Figure 11: Variable distributions in the same-sign control region of the b-tag category. The integrated luminositycorresponds to 3.21 fb−1. The signal is normalised to 1 pb−1 for illustration purpose: (a) Leading τhad pT, (b)Leading τhad η, (c) Sub-leading τhad pT, (d) Sub-leading τhad η, (e)Emiss
T , (f) ΣET.
9th May 2016 – 16:38 26
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
>20 GeV)T
p (bjetN
Eve
nts/
1
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
>20 GeV)T
p (bjetN0 1 2 3 4 5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]jet0
Tp
Eve
nts/
83
GeV
1−10
1
10
210
310 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]jet0
Tp
0 50 100 150 200 250 300 350 400 450 500Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,0τ (Tm
Eve
nts/
75
GeV
1−10
1
10
210
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
) [GeV]missTE,0τ (Tm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
) [GeV]missTE,1τ (Tm
Eve
nts/
40
GeV
1−10
1
10
210
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
ττmvis
Eve
nts/
GeV
3−10
2−10
1−10
1
10 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
ττmvis0 200 400 600 800 1000 1200D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TotTm
Eve
nts/
GeV
3−10
2−10
1−10
1
10 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]TotTm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(f)
Figure 12: Variable distributions in the same-sign control region of the b-tag category. The integrated luminositycorresponds to 3.21 fb−1. The signal is normalised to 1 pb−1 for illustration purpose: (a) Nb−jet, (b) Leading jet pT,(c) mT(τ0, Emiss
T ), (d) mT(τ1, EmissT ), (e) mvis, (f) mtot
T .
9th May 2016 – 16:38 27
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV] 0τT
p
Eve
nts/
15
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV] 0τT
p100 150 200 250 300 350 400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]0τη
Eve
nts/
0.5
GeV
10
20
30
40
50
60
70
80 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]0τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(b)
[GeV] 1τT
p
Eve
nts/
22
GeV
1−10
1
10
210
310
410=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV] 1τT
p50 100 150 200 250 300 350 400 450D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(c)
[GeV]1τη
Eve
nts/
0.5
GeV
10
20
30
40
50
60
70
80=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(d)
[GeV]missTE
Eve
nts/
20
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]missTE
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TsumE
Eve
nts/
50
GeV
1−10
1
10
210
310
410=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]TsumE0 200 400 600 800 100012001400160018002000D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(f)
Figure 13: Variable distributions in the same-sign control region of the b-veto category. The integrated luminositycorresponds to 3.21 fb−1. The signal is normalised to 1 pb−1 for illustration purpose: (a) Leading τhad pT, (b)Leading τhad η, (c) Sub-leading τhad pT, (d) Sub-leading τhad η, (e)Emiss
T , (f) ΣET.
9th May 2016 – 16:38 28
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
>20 GeV)T
p (bjetN
Eve
nts/
1
1−10
1
10
210
310
410=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
>20 GeV)T
p (bjetN0 1 2 3 4 5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]jet0
Tp
Eve
nts/
25
GeV
1−10
1
10
210
310
410=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]jet0
Tp
0 50 100 150 200 250 300 350 400 450 500Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,0τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
) [GeV]missTE,0τ (Tm
0 100 200 300 400 500 600Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
ττmvis
Eve
nts/
50
GeV
1−10
1
10
210
310
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
ττmvis0 200 400 600 800 1000 1200 1400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TotTm
Eve
nts/
GeV
3−10
2−10
1−10
1
10
210=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(f)
Figure 14: Variable distributions in the same-sign control region of the b-veto category. The integrated luminositycorresponds to 3.21 fb−1. The signal is normalised to 1 pb−1 for illustration purpose: (a) Nb−jet, (b) Leading jet pT,(c) mT(τ0, Emiss
T ), (d) mT(τ1, EmissT ), (e) mvis, (f) mtot
T .
9th May 2016 – 16:38 29
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
110
1
10
210
310
410
510
610
710
eve
nts
Dataττ→*γZ/
QCDντ→W
TopOthers
ττ→(0.500TeV)SSMZ’ττ→(1.000TeV)SSMZ’ττ→(1.500TeV)SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫
InternalATLAS Dataττ→*γZ/
QCDντ→W
TopOthers
ττ→(0.500TeV)SSMZ’ττ→(1.000TeV)SSMZ’ττ→(1.500TeV)SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫
InternalATLAS Dataττ→*γZ/
QCDντ→W
TopOthers
ττ→(0.500TeV)SSMZ’ττ→(1.000TeV)SSMZ’ττ→(1.500TeV)SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫
InternalATLAS Dataττ→*γZ/
QCDντ→W
TopOthers
ττ→(0.500TeV)SSMZ’ττ→(1.000TeV)SSMZ’ττ→(1.500TeV)SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫
InternalATLAS
0.5
1
1.5
[GeV]totTm
200 300 400 500
Da
ta/M
C
stat. syst.stat. syst.stat. syst.stat. syst.stat. syst.stat. syst.stat. syst.stat. syst.
Figure 15: mtotT distribution in the inclusive category in the same sign region including exemplary Z ′signals for
mZprime of 0.5, 1.0 and 1.5 TeV stacked on top of the SM background. The x-axis is in logarithmic scale and binshave been sized equally in that scale. The last bin includes the overflow bin. The distribution correspond to anintegrated luminosity of 1 fb−1.
9th May 2016 – 16:38 30
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
5. Background Estimation404
The dominant background is multi-jet production, whose cross section is several orders of magnitude405
higher than that of the signal processes. Despite the big suppression of this background due to the event406
selection, a sizeable contribution remains, therefore its estimation is very important for this analysis. This407
process contributes to the final distribution because in a fraction of events two jets are misidentified as408
hadronically decaying tau leptons. Since the theoretical description of multi-jet processes at the LHC409
is not sufficiently advanced, the background is estimated using a data-driven method. This technique is410
described in detail in Sec. 5.1.411
All of the following background processes are estimated using Monte Carlo simulation.412
A background contribution comes fromW (→ τν)+jets events, where one of the additional jets is misiden-413
tified as a τhad-vis.414
Other backgrounds from W decays arise when the muon or electron along with at least one additional jet415
in W (→ `ν)+jets are misidentified as hadronically decaying tau leptons. Due to the electron and muon416
veto this background is highly suppressed.417
A significant and irreducible background contribution arises from Z/γ∗ → ττ processes where both tau418
leptons decay hadronically.419
Due to the lepton veto Z decays to two electrons or muons play a very minor role.420
Since top quarks predominantly haveW bosons in their decay final states, tt aswell as single-top production,421
can pass the event selection. This happens when both top quarks in tt have true τhad-vis final states or due422
to misidentified leptons or jets.423
Also in di-boson production processes pairs of misidentified τhad-vis can emerge.424
5.1. Data-driven QCD background estimation425
A control region, which almost exclusively contains multi-jet events, is obtained by inverting the tau ID426
requirement of the leading τhad-vis. Fake factors, depending on pT(τhad-vis) and the number of tracks in the427
tau core region, are obtained in a tag-and-probe analysis.428
The tau ID fake factors, fτ−ID, are defined as the number of probe-jets in the di-jet analysis that pass tau429
ID, Npass τ−ID, divided by the number that fail, N fail τ−ID:430
fτ−ID(pT, Ntrack) ≡Npass τ−ID(pT, Ntrack)N fail τ−ID(pT, Ntrack)
di−jet. (1)
The shape and normalisation of the multijet contribution where the sub-leading tau candidate passes tau431
ID, Nmultijet, in a given kinematic variable ‘x’, is predicted by weighting the events where the sub-leading432
tau candidate fails tau ID by their fake factor:433
Nmultijet(pT, Ntrack, x) = fτ−ID(pT, Ntrack) ×(N fail τ−ID
data(pT, Ntrack, x))
A correction for the contamination of the fail-ID region with non-multijet backgrounds is applied by434
subtracting the Monte Carlo estimated backgrounds weighted by the fake factors. The tau ID fake factors435
9th May 2016 – 16:38 31
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
aremeasured using a dijet tag and probe analysis, designed to be as similar to the signal selection as possible,436
while avoiding contamination from real taus. The analysis considers events which fire one of the single437
jet triggers (HLT_j460, HLT_j440, HLT_j420, HLT_j400, HLT_j380, HLT_j360, HLT_j330, HLT_j320,438
HLT_j300, HLT_j260, HLT_j200, HLT_j175, HLT_j150, HLT_j110, HLT_j85, HLT_j60, HLT_j55,439
HLT_j35, HLT_j25) Events are required to contain at least two tau candidates with pT > 55 GeV. The440
leading tau is defined as the tag and the sub-leading as the probe. The tag is required to have pT > 100 GeV,441
and pass a tight electron veto. A loose pT balance is applied such that the pT of the sub-leading tau is at442
least 30% of the leading tau pT. Some selection criteria have been relaxed with respect to the signal region443
definition to increase sensibly the statistics of the control region, after verifying that this has no impact444
on the fake factor measurement within statistical uncertainties. Events with taus of opposite and same445
charge are simultaneously considered in the fake factors measurement. Consistency of the fake factors for446
same-sign and opposite-sign configurations of the two leading τhad has been checked and good agreement447
is found within statistical uncertainties. No requirement is applied on the number of tracks in the tau448
core region for the leading tau candidate, nor on the transverse plane distance ∆φ between the tag and the449
probe. Fake factors are determined as a function of τhad pT. Table 7 shows the cutflow corresponding to450
the dijet control region event selection.451
(a)
Figure 16: Distribution of the ∆φ(ττ) versus the ratio of the pT of the sub-leading tau divided by the leading tau pTin the multi-jet control region before applying the selection criteria on those variables.
Figure 16 shows the distribution of the ∆φ(ττ) versus the ratio of the pT of the sub-leading tau divided by452
the leading tau pT in the multi-jet control region before applying these two selection criteria. The events453
selected for the fake factor measurement are located in the top right corner.454
Figure 17 shows the fake factors for 1-prong and 3-prong probe tau candidates. These are displayed for455
scenarios where the charges of the leading and subleading jets are opposite sign, same sign and inclusive.456
Figure 18 shows the distribution of the pT of all τhad in various regions. As described above the shape of457
the multijet estimation in the signal region (shown in Subfig. a) is taken from the control region where458
the subleading τhad fails the ID criterion (shown in Subfig. b). For validation the same is shown for the459
pass-ID and fail-ID regions where the two leading τhad have the same charge.460
9th May 2016 – 16:38 32
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
The fake factors have been evaluated for events fulfilling the b-tag requirement and failing it. Figure 19461
shows the fake factor distributions for events passing and failing the b-tag requirement: a significant462
difference between the two classes of events is observed for 1-prong probes. A smaller, but still non-463
negligible difference is observed for 3-prong events. Therefore fake factors are determined separately for464
the b-tag and b-veto categories.465
Cut dataPreselection 137486jet trigger 137440tag pT 100 GeV 51357probe pT> 55 GeV 32210pprobeT > 0.3xptagT 21764∆φ 102681-prong 1605Pass loose BDT jet score 164Fail loose BDT jet score 14413-prong 8663Pass loose BDT jet score 49Fail loose BDT jet score 8614
Table 7: Observed number of events in the dijet control region for 3.21 fb−1. The Control region is divided between1-prong and 3-prong candidate taus passing or failing the loose BDT jet ID requirement
(a) (b)
Figure 17: Inclusive TAU ID fake factors fτ−IDfor 1-prong (left) and 3-prong (right) tau candidates, as measured inthe dijet tag and probe analysis, and separated by the charge product of the two candidates.
5.1.1. Multi-jet Validation Region466
The validation of multi-jet fake factor measurement is performed in the multi-jet validation region. The467
region is defined by applying the selection criteria outlined at the beginning of this section with the468
exception that the sub-leading τhadis required to pass the loose ID requirement:469
470
9th May 2016 – 16:38 33
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
) [GeV]1τ (T
p100 200 300 400 500 600 700 800 900 1000
0
0.05
0.1
0.15
0.2
0.251-prong
< 2.7φ∆ > 2.7φ∆
1-prong
(a)
) [GeV]1τ (T
p100 200 300 400 500 600 700 800 900 1000
0
0.01
0.02
0.03
0.04
0.05
3-prongs
< 2.7φ∆ > 2.7φ∆
3-prongs
(b)
) [GeV]1τ (T
p100 200 300 400 500 600 700 800 900 1000
0
0.02
0.04
0.06
0.08
0.1
0.12
0.14
0.16
0.18
0.2
0.221-prong
1-prong or 3-prong Tag
No track requirement
1-prong
(c)
) [GeV]1τ (T
p100 200 300 400 500 600 700 800 900 1000
0
0.002
0.004
0.006
0.008
0.01
0.012
0.014
0.0163-prongs
1-prong or 3-prong Tag
No track requirement
3-prongs
(d)
Figure 18: Comparison of fake factor measurement for different selection criteria: (a) ∆φ selection comparisonfor 1-prong tau candidates , (b) ∆φ selection comparison for 3-prong candidates, (c) Ntrk selection comparison for1-prong candidates (d) Ntrk selection comparison for 3-prong candidates.
(a) (b)
Figure 19: TAU ID fake factors fτ−IDof 1-prong (left) and 3-prong (right) tau candidates for events passing andfailing the b-tag requirement.
• fire one of the single jet triggers (HLT_j460, HLT_j440, HLT_j420, HLT_j400, HLT_j380,471
HLT_j360, HLT_j330, HLT_j320, HLT_j300, HLT_j260, HLT_j200, HLT_j175, HLT_j150, HLT_j110,472
HLT_j85, HLT_j60, HLT_j55, HLT_j35, HLT_j25)473
474
9th May 2016 – 16:38 34
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
• Events are required to contain at least two tau candidates with pT > 55 GeV.475
476
• The leading tau is required to have pT > 100 GeV, and pass a tight electron veto.477
478
• The leading tau is required to fail the medium identification requirement.479
480
• The sub-leading tau is required to pass the loose identification requirement481
• pT balance: pT of the sub-leading tau is at least 30% of the leading tau pT.482
483
The multi-jet background in this validation region is evaluated by applying the fake factor method, hence484
providing a closure check of the multi-jet estimation method.485
[GeV] 0τT
p
Eve
nts/
14
GeV
10
20
30
40
50
60
70
80
90Multi-jet Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/A
[GeV] 0τT
p150 200 250 300 350 400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV] 1τT
p
Eve
nts/
22
GeV
20
40
60
80
100
120 Multi-jet Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/A
[GeV] 1τT
p50 100 150 200 250 300 350 400 450D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(b)
[GeV]1τη
Eve
nts/
0.5
GeV
20
40
60
80
100
120 Multi-jet Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/A
[GeV]1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(c)
>25 GeV)T
p (jetN
Eve
nts/
1
1−10
1
10
210
310
410Multi-jet Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/A
>25 GeV)T
p (jetN0 2 4 6 8 10 12D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(d)
Figure 20: Validation region distributions: (a) leading τhad pT, (b) sub-leading τhad pT, (c) sub-leading τhad η, (d)Njet.
9th May 2016 – 16:38 35
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]TsumE
Eve
nts/
50
GeV
10
20
30
40
50
60
70
80
90Multi-jet Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/A
[GeV]TsumE0 200 400 600 800 100012001400160018002000D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(a)
[GeV]missTE
Eve
nts/
10
GeV
20
40
60
80
100
120
140
160
180 Multi-jet Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/A
[GeV]missTE
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
ττmvis
Eve
nts/
50
GeV
10
20
30
40
50
60
70
80
90 Multi-jet Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/A
ττmvis0 200 400 600 800 1000 1200 1400D
ata/
Bkg
Rat
io
0.20.40.60.8
11.21.41.61.8
(c)
[GeV]TotTm
Eve
nts/
GeV
0.5
1
1.5
2
2.5
3Multi-jet Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/A
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
Figure 21: Validation region distributions: (a) ΣET, (b) EmissT , (c) visible mass mvis
ττ , (d) mTotT .
Figs 20 and 21 show the distributions of the taus kinematics and event variables in the multi-jet validation486
region.487
5.2. W (→ τν)+jets background estimation488
Additional to the correction using the fake rates described in Section 5.3, special care has to be taken489
to estimate the W (→ τν)+jets background. In order that enough events remain after the event selection490
for a sufficient modelling of the W (→ τν)+jets background, Sherpa-generated samples that are split up491
using cuts on the W pT at the level of the matrix element calculation are used. This slicing of the sample492
phase space enhances the statistical population of events in regions relevant for this analysis significantly.493
Samples sliced in boson mass instead, generated by Powheg and showered using Pythia8, were tested, too,494
but the number of events in the signal region was far too small to estimate the background correctly. In the495
Sherpa samples modelling issues were observed and corrected as described in the following sections.496
9th May 2016 – 16:38 36
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
5.2.1. Simulation of spin effects497
The version of Sherpa used to generate the samples exceeded the acceptable generation time and hence498
the spin correlation of the W and its decay products was switched off. This results in incorrectly modelled499
tau decay distributions. To correct this the W (→ τν)+jets events are weighted using the TauSpinner500
program [75–77], developed to simulate spin effects in taus from boson decays. A validation of this501
reweighting at generator level for Sherpa is described in [78], the key plots are shown in Fig 22.502
)0π+E±π
)/(E0π-E±π
= (EΥ-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
Υ1/
N d
N/d
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035τν0h±h→±τ
Sherpa
Sherpa + TauSpinner
Powheg
ATLAS Internal
(a)
)0π+E±π
)/(E0π-E±π
= (EΥ-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
Υ1/
N d
N/d
0
0.01
0.02
0.03
0.04
0.05
τν02h±h→±τSherpa
Sherpa + TauSpinner
Powheg
ATLAS Internal
(b)
)0π+E±π
)/(E0π-E±π
= (EΥ-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
Υ1/
N d
N/d
0
0.01
0.02
0.03
0.04
0.05
0.06
0.07
τν0h±3h→±τSherpa
Sherpa + TauSpinner
Powheg
ATLAS Internal
(c)
*)θcos(
-1 -0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 1
*)θ1/
N d
N/d
cos(
0
0.005
0.01
0.015
0.02
0.025
0.03
0.035 decaysτall
Sherpa
Sherpa + TauSpinner
Powheg
ATLAS Internal
(d)
Figure 22: Validation plots for TauSpinner reweighting of W (→ τν)+jets Sherpa samples. The reweighted distri-butions are compared to corresponding Powheg samples. The Y variable corresponds to the asymmetry betweenthe energy of charged and neutral hadrons in the tau decay. [78]
5.2.2. Sherpa Shape Reweighting503
The W+jets description for Sherpa and Powheg samples is compared in a W (→ µν)+jets control region.504
Based on lepton universality, the selection is representative for the main region.505
The same data quality requirements (GRL, error flags) as in the main selection (cf. 4) are required. Events506
are triggered by either one of the single muon triggers HLT_mu24_iloose_L1Mu15 and HLT_mu50. After507
the tau candidates are selected to have at least 55GeVin pT, additionally to the preselection criteria508
described in Section 3.1, the event is required to have at least one remaining τhad-vis candidate. A veto of509
9th May 2016 – 16:38 37
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
events with electrons with pT > 15GeVand loose LLH identification is applied. There has to be exactly510
one muon with pT > 110GeV, medium quality and matched to the trigger for the event to pass. Events511
with additional muons with pT > 7GeVand loose quality are vetoed. To reduce contributions from the512
multijet background, the muon has to be isolated using a gradient isolation algorithm which is expected513
to be 90(99)% efficient for muons of pT = 25(60) GeV. To suppress the multijet contamination, a cut on514
∆φ > 2.4 is applied.515
A clear disagreement between data and background prediction is observed when using Sherpa to simulate516
the W (→ µν)+jets contribution. In Figures 23 and 24 some distributions are shown for comparison using517
Powheg and Sherpa.518
even
ts
1
10
210
310
410
510DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pµ50 100 150 200 250 300 350 400 450 500
Dat
a/M
C
0.5
1
1.5stat.stat.stat.stat.
(a)
even
ts
10
210
310
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pτ50 100 150 200 250 300
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(b)ev
ents
1
10
210
310
410DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]missTE
0 50 100 150 200 250 300 350 400
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(c)
even
ts
1
10
210
310
410
510DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pµ50 100 150 200 250 300 350 400 450 500
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(d)
even
ts
10
210
310
410 DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pτ50 100 150 200 250 300
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(e)
even
ts
1
10
210
310
410DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]missTE
0 50 100 150 200 250 300 350 400
Dat
a/M
C
0
1
2
3 stat.stat.stat.stat.
(f)
Figure 23: Distributions for muon pT (a, d), tau pT (b, e) and EmissT (c, e) are shown with W+jets estimation by
Sherpa (top) and Powheg (bottom).
To correct for this behaviour a reweighting function is determined, to be applied on the W (→ τν)+jets519
Sherpa samples in the signal region and same-sign control region. A one-dimensional exponential520
correction in dependence of the total transversemass proved to yield the best results. The resulting function521
is exp(a+ b×mtotT ), with mtot
T given in GeV and a = 0.321±0.053, b = −(2.03±0.17)×10−3 GeV−1. It is522
obtained by fitting the ratio of the difference of data and all background predictions besidesW (→ µν)+jets523
to the MC estimate for W (→ µν)+jets. 3 As shown in Fig. 25 the correction results in a greatly improved524
description for all considered observables.525
3 This reweighting procedure changed compared to the preliminary result of December 2015. Before the reweighting wasdetermined using the ratio between PowhegPythia8 and Sherpa W+jets samples. Additionally a global scale factor and
9th May 2016 – 16:38 38
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
even
ts
1
10
210
310
410DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]totTm
100 200 300 400 500 600 700 800 900 1000
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(a)ev
ents
10
210
310
410DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]Tm0 50 100 150 200 250 300
Dat
a/M
C
0.5
1
1.5stat.stat.stat.stat.
(b)
even
ts
1
10
210
310
410
510DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
φ ∆ cos ∑1− 0.8− 0.6− 0.4− 0.2− 0 0.2 0.4 0.6 0.8 1
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(c)
even
ts
1
10
210
310
410
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]totTm
100 200 300 400 500 600 700 800 900 1000
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(d)
even
ts
10
210
310
410DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]Tm0 50 100 150 200 250 300
Dat
a/M
C
0.6
0.8
1
1.2
1.4stat.stat.stat.stat.
(e)
even
ts
1−10
1
10
210
310
410
510 DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
φ ∆ cos ∑1− 0.8− 0.6− 0.4− 0.2− 0 0.2 0.4 0.6 0.8 1
Dat
a/M
C0.5
1
1.5 stat.stat.stat.stat.
(f)
Figure 24: Distributions for mtotT (a, d), mT
(µ, Emiss
T
)(b, e) and
∑cos∆φ (c, e) are shown with W+jets estimation
by Sherpa (top) and Powheg (bottom).
5.3. Modelling of fake taus in MC backgrounds526
Backgrounds that are estimated using Monte Carlo simulation mostly contain at least one jet that is527
misidentified as a τhad-vis. As shown in Fig. 26 and 27, the tau misidentification efficiency (fake rate) is not528
modelled well in Monte Carlo events and therefore a data-driven correction is applied to the Monte Carlo.529
For τhad-vis in MC that are known to be misidentified, i.e. they are not truth-matched, instead of checking530
the jet BDT rejection discriminant, a fake rate is applied as an event weight. In addition to correcting the531
background yield this also increases the statistics of these fake backgrounds, allowing for a more precise532
description especially in the high energy tails of the distributions.533
In a control region similar to the W (→ µν)+jets region described in Sec. 5.2.2, but lower pT thresholds534
(muon pT > 55 GeV, tau pT > 50 GeV), the fake rates are measured separately for top and W (→ µν)+jets535
backgrounds.536
The further selection for the W (→ µν)+jets control region is described in Sec. 5.3.1, for the top control537
region in Sec. 5.3.2.538
uncertainty was applied, which according to more recent studies is no longer necessary.
9th May 2016 – 16:38 39
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
even
ts
1
10
210
310
410
510DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pµ50 100 150 200 250 300 350 400 450 500
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(a)ev
ents
10
210
310
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pτ50 100 150 200 250 300
Dat
a/M
C
0.60.8
1
1.21.4
stat.stat.stat.stat.
(b)
even
ts
1
10
210
310
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]missTE
0 50 100 150 200 250 300 350 400
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(c)
even
ts
1
10
210
310
410DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]totTm
100 200 300 400 500 600 700 800 900 1000
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(d)
even
ts
10
210
310
410DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]Tm0 50 100 150 200 250 300
Dat
a/M
C
0.8
1
1.2stat.stat.stat.stat.
(e)
even
ts
1
10
210
310
410
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLASData
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
φ ∆ cos ∑1− 0.8− 0.6− 0.4− 0.2− 0 0.2 0.4 0.6 0.8 1
Dat
a/M
C0.5
1
1.5 stat.stat.stat.stat.
(f)
Figure 25: Distributions for muon pT (a), tau pT (b) and EmissT (c), mtot
T (d), mT(µ, Emiss
T
)(e) and
∑cos∆φ (f) are
shown after applying a reweighting determined from data in mtotT to the Sherpa W (→ µν)+jets.
5.3.1. W (→ µν)+jets control region539
To further suppress the multijet contamination, cuts on∑`=µ,τ cos∆φ(`, Emiss
T ) < 0 and ∆φ > 2.4 are540
applied. On top of that, events with b-tagged jets are vetoed, primarily reducing the amount of top541
background. The same definition of b-tagged jets as in the main analysis is used.542
The selection results in a purity of 88%W (→ µν)+jets, measured as the number of events in Monte Carlo543
divided by the data yield. In Fig. 28 there are distributions of several event observables in this control544
region.545
5.3.2. Top control region546
A control region with 81% purity is achieved by requiring at least one b-tagged jet, using the same b-jet547
identification as in the main analysis. Distributions of this control region are shown in Fig. 29.548
This control region has a similar composition of top Monte Carlo samples as the signal region. The549
fraction of tt is 89% in both cases. The control region has 7% Wt and 4% single-top, while the signal550
region has 10% Wt and 1% single-top.551
9th May 2016 – 16:38 40
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0.1
0.15
0.2
0.25
0.3
0.35 data
top MC = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(a) 1-prong opposite-sign
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0
5
10
15
20
25
30
3−10×
data
top MC = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(b) 3-prong opposite-sign
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0.05
0.1
0.15
0.2
0.25data
top MC = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(c) 1-prong same-sign
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
2
4
6
8
10
12
14
16
18
20
22
3−10×
data
top MC = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(d) 3-prong same-sign
Figure 26: Shown is the fake rate for the loose ID working point in the top control region in data compared to thetop Monte Carlo sample. It is split into opposite-sign (top) and same-sign (bottom), as well as 1-prong (left) and3-prong (right)
The top control region has a significant contamination of true tau background. For the fake rate calculation552
this contribution is subtracted using Monte Carlo prediction.553
5.3.3. Fake Rate Measurements554
The tau trigger also applies a jet BDT similar to the offline tau identification BDT and is behaving555
differently on Monte Carlo. Therefore, if the leading tau is not truth-matched, the trigger is not applied556
and instead a fake rate that includes the trigger criterion is applied. To check the result of the online tau ID,557
the subleading tau is matched to the resurrected trigger decision of the HLT_tau25_medium1_tracktwo558
trigger, which uses the same jet BDT as the single-tau trigger used for the main selection. The fake rates559
are binned in the pT of the τhad-vis and are measured for the same-sign and opposite-sign categories, for560
9th May 2016 – 16:38 41
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0.08
0.1
0.12
0.14
0.16
0.18
0.2data
W MC = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(a) 1-prong opposite-sign
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
5
10
15
20
25
30
35
40
453−10×
data
W MC = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(b) 3-prong opposite-sign
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0.05
0.1
0.15
0.2
0.25
data
W MC = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(c) 1-prong same-sign
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0
2
4
6
8
10
12
14
16
18
3−10×
data
W MC = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(d) 3-prong same-sign
Figure 27: Shown is the fake rate for the loose ID working point in the W (→ µν)+jets control region in datacompared to the W (→ µν)+jets Monte Carlo sample. It is split into opposite-sign (top) and same-sign (bottom), aswell as 1-prong (left) and 3-prong (right)
1prong and 3prong taus each. In Fig. 30 the fake rates for loose (to be applied for fake subleading taus)561
and medium+trigger (to be applied for fake leading taus) are shown. The fake rates measured for W+jets562
are applied to other MC backgrounds, besides top, as well.563
In the region with a b-tag cut theW (→ µν)+jets process is no longer the leading contribution and therefore564
it is not feasible to explicitly measure W+jets fake rates for the b-tag category. To estimate the difference565
of these fake rates between b-tag and b-veto categories, the fraction of quark initiated jets that are matched566
to the tau candidate is studied in Monte Carlo, since this fraction is the main determinant of the fake rate.567
As shown in Fig. 31 there is no significant difference in the fraction of tau fakes matched to a quark jet568
between an inclusive and b-tagged selection and therefore fake rates measured in the b-veto control region569
are applicable in b-tag regions as well.570
However, the fraction of quark → tau fakes is different between top and W backgrounds (cf. Fig. 32),571
9th May 2016 – 16:38 42
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
even
ts
1
10
210
310
410
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]totTm
100 200 300 400 500 600 700 800 900 1000
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(a)
even
ts
10
210
310
410
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pτ50 100 150 200 250 300
Dat
a/M
C
0.8
1
1.2stat.stat.stat.stat.
(b)
even
ts
1
10
210
310
410
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pµ50 100 150 200 250 300 350 400 450 500
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(c)
even
ts
1
10
210
310
410
DataWmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
WmunuTopWtaunuZmumuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]missTE
0 50 100 150 200 250 300 350 400
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(d)
Figure 28: Event observables in the W (→ µν)+jets control region. Reweighted Sherpa samples are used for theW+jets background. Plotted are: mtot
T (a), τpT (b), muon pT (c) and EmissT (d)
which results in different fake rates and emphasises the importance of the separate control regions. The572
W (→ τν)+jets fake fraction measurement suffers from low statistics, especially in the b-tagged category.573
However, the W (→ τν)+jets background plays a very minor role in the b-tag category.574
6. Systematic Uncertainties575
6.1. Luminosity576
The integrated luminositymeasurement has an uncertainty of 5%. This systematic uncertainty is applied to577
all the signal and backgrounds processes with the exception of the QCD background, which it is estimated578
from data.579
9th May 2016 – 16:38 43
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
even
ts
1−10
1
10
210
310
410DatattbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
ttbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
ttbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]totTm
100 200 300 400 500 600 700 800 900 1000
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(a)
even
ts
10
210
310
DatattbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
ttbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
ttbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pτ50 100 150 200 250 300
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(b)
even
ts
1−10
1
10
210
310
410DatattbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
ttbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
ttbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]T
pµ50 100 150 200 250 300 350 400 450 500
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(c)
even
ts
1−10
1
10
210
310
410DatattbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
ttbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Data
ttbarWtSingleTopWmunuOthers
= 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
[GeV]missTE
0 50 100 150 200 250 300 350 400
Dat
a/M
C
0.5
1
1.5 stat.stat.stat.stat.
(d)
Figure 29: Event observables in the top control region. Reweighted Sherpa samples are used for the W+jetsbackground. Plotted are: mtot
T (a), τpT (b), muon pT (c) and EmissT (d)
6.2. Detector-related uncertainties580
Uncertainties relating to the detector simulation are included for signal and for backgrounds that are581
estimated using simulated samples. These systematics include uncertainty associated with:582
• the τhad reconstruction and identification efficiencies,583
• the τhad trigger scale factor,584
• the τhad electron veto,585
• the electron and muon trigger, reconstruction and identification efficiencies,586
• jet, electron, muon and τhad energy scales,587
• jet energy resolution and calibration,588
9th May 2016 – 16:38 44
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0.05
0.1
0.15
0.2
0.25
0.3
0.35 SS top
OS top
SS W+jets
OS W+jets = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(a) Loose-ID 1-prong
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0
5
10
15
20
25
30
3−10×
SS top
OS top
SS W+jets
OS W+jets = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(b) Loose-ID 3-prong
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0
0.05
0.1
0.15
0.2
0.25
0.3 SS top
OS top
SS W+jets
OS W+jets = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(c) Trigger+Medium-ID 1-prong
[GeV]T
pτ50 100 150 200 250 300
fake
rat
e
0
2
4
6
8
10
12
14
163−10×
SS top
OS top
SS W+jets
OS W+jets = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
(d) Trigger+Medium-ID 3-prong
Figure 30: Tau fake rates measured in the W (→ µν)+jets and top control regions in data for the loose working point(top) and medium working point including the trigger (bottom). It is split in 1-prong (left) and 3-prong (right) andaccording to the charge product of the two leading taus.
• calibration of the EmissT ,589
• jet flavour tagging systematics.590
Any systematic effect on the the overall normalisation or shape of the mTotT distribution in the signal region591
is considered. These uncertainties are also taken into account for simulated samples that are used in the592
development of data-driven methods. The electron, muon, jet and EmissT systematics described above are593
found to produce negligible effect in the signal region. The dominant largest up and down systematic594
deviations in MC background and signal are shown in Tables 8 and 9 for the tagged and veto categories,595
respectively. Figure. 33 shows the effect of the τ energy scale systematic on a gluon fusion signal sample,596
as well as various MC background, where a shape systematic is clearly visible in the former. AtlasFast-II597
simulation has been used for the detector simulation of the bbH samples and corresponding detector598
uncertainties have been used. The tau reconstruction and energy scale uncertainties contain additional599
9th May 2016 – 16:38 45
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]T
pτ50 100 150 200 250 300
rela
tive
diffe
renc
e
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8Top
ντ→W
= 13 TeVs SimulationATLAS
(a) opposite sign
[GeV]T
pτ50 100 150 200 250 300
rela
tive
diffe
renc
e
0.2
0.4
0.6
0.8
1
1.2
1.4
1.6
1.8Top
ντ→W
= 13 TeVs SimulationATLAS
(b) same sign
Figure 31: Relative difference of fractions of fake subleading taus that are matched to a quark-initiated jet, for theb-tag divided by inclusive category.
[GeV]T
pτ50 100 150 200 250 300
frac
tion
0.4
0.5
0.6
0.7
0.8
0.9
1
1.1
Top
ντ→W
= 13 TeVs
SimulationATLAS
(a) opposite sign
[GeV]T
pτ50 100 150 200 250 300
frac
tion
0.75
0.8
0.85
0.9
0.95
1
1.05
Top
ντ→W
= 13 TeVs SimulationATLAS
(b) same sign
Figure 32: Fraction of fake subleading taus that are matched to a quark-initiated jet for opposite sign (left) andsame-sign (right) for top and W (→ τν)+jets for the inclusive selection.
high-pT uncertainties.600
Using the b-tag and b-veto categories introduces additional systematics uncertainties on the event selection601
and final distributions. These come from the jets themselves as well as from flavour tagging of the jets.602
These systematics where assessed in both signal and control regions and are tested for normalisation and603
shape effects. Grouped jet systematic distributions for the tagged and veto signal regions for different604
backgrounds are shown in Figure. 34 and don’t show a statistically significant systematic effect. The605
effect of uncertainties in the flavour tagging scale factors where also accessed in both the tagged and veto606
categories and found to be negligible, as seen in Figure. 35607
9th May 2016 – 16:38 46
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Table 8: The effect in % of the dominant detector systematic uncertainties on the final event yield in backgroundevents passing the b-tag event selection. Many systematic uncertainties that have little effect (< 1 %) on overallyield are not shown.
b-tagSystematic QCD Top Wtaunu Ztautau Others bbH (500 GeV) ggH (500 GeV)
fake factor 17.1−17.1 - - - - - -
τ trigger −1.61.9
18.0−15.4
7.2−6.1
21.9−19.3
8.4−7.4
26.3−24.1
24.9−22.3
τ ID - 10.9−10.3
6.2−6.2
12.6−11.9
3.9−3.9
12.0−11.3
11.8−11.1
τ ID high-pT - 1.0−1.0 - 1.6
−1.6 - 2.4−2.4
2.2−2.2
τ e-veto - 2.7−2.7
1.5−1.5
3.3−3.2
1.0−1.0
4.7−4.7
4.0−3.9
τ Reco - 3.9−3.8
2.5−2.5
4.7−4.6
1.5−1.5
4.5−4.4
4.6−4.5
TES “DETECTOR” - 8.6−7.4
4.5−4.8
4.9−10.8
0.0−0.8
1.8−2.2
0.0−4.5
TES “MODEL” - 1.8−0.4
0.9−1.7
2.6−0.1
0.0−0.0
0.3−0.4
0.0−0.0
TES “INSITU” - 6.8−4.3
2.3−6.7
4.5−6.8
0.0−1.0
1.2−1.3
0.0−0.9
fake rate - 4.9−5.7
9.3−8.5 - 12.4
−11.0 - -
pileup reweighting - 3.6−3.4
−15.52.1
−5.14.6
−25.92.1
3.8−1.7
6.51.3
JVT SF - 3.9−3.7
3.9−3.7
2.9−2.9
4.6−4.4
3.4−3.3
3.6−3.5
btag eff. (L 0) - - −3.83.8
−4.54.5
−7.67.6 - −5.9
5.9
btag eff. (L 1) - - - - - - −1.21.2
btag eff. (B 0) - −2.22.1
−2.32.3
−1.91.9
−1.41.3
−3.63.6
−2.82.8
btag eff. (C 0) - - −4.64.6
−4.14.2
−3.93.8 - −3.1
3.0
btag eff. (C 1) - - 2.5−2.5
2.4−2.4
2.2−2.2 - 2.0
−2.0JES NP 1 - 0.0
−0.50.8−0.1
2.7−1.9
0.3−0.2
1.2−1.3
1.4−3.1
JES NP 2 - 0.0−0.0
0.0−0.3
0.0−0.1
0.1−0.1
0.4−0.0
0.0−0.0
JES NP 3 - 0.0−0.0
0.1−0.2
0.0−0.1
0.0−0.1
0.5−0.0
2.0−2.0
JER - 0.6−0.6
1.0−1.0
1.6−1.6
5.9−5.9
0.7−0.7
0.5−0.5
9th May 2016 – 16:38 47
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Table 9: The effect in % of the dominant detector systematic uncertainties on the final event yield in backgroundevents passing the full b-veto event selection. Many systematic uncertainties that have little effect (< 1 %) on overallyield are not shown.
b-vetoSystematic QCD Top Wtaunu Ztautau Others bbH (500 GeV) ggH (500 GeV)
fake factor 6.8−6.8 - - - - - -
τ trigger - 18.3−15.9
5.6−4.6
21.1−18.2
11.9−10.4
26.0−23.9
25.7−23.5
τ ID - 10.5−10.0
6.6−6.6
12.5−11.8
6.9−6.5
12.0−11.4
11.9−11.2
τ ID high-pT - 1.0−1.0 - 1.5
−1.4 - 2.3−2.3
2.3−2.2
τ e-veto - 2.7−2.6
1.3−1.3
3.3−3.2
1.7−1.7
4.7−4.7
3.8−3.8
τ Reco - 3.8−3.7
2.4−2.4
4.6−4.5
2.6−2.5
4.5−4.4
4.5−4.4
TES “DETECTOR” - 6.7−6.2
5.4−4.6
11.0−10.1
6.1−3.6
1.4−1.5
2.0−2.3
TES “MODEL” - 0.8−1.9
1.2−0.0
1.4−1.6
2.0−0.7
0.3−0.5
0.4−0.5
TES “INSITU” - 5.8−5.5
4.3−2.4
6.3−4.9
3.5−2.4
0.9−0.8
1.2−1.4
fake rate - 5.4−6.2
9.5−8.7 - 8.0
−7.0 - -
pileup reweighting - −3.84.3
6.11.7 - −1.5
1.2 - 1.1−0.6
JVT SF - 3.6−3.4
2.1−2.0
1.2−1.2
1.9−1.8
1.8−1.8
1.7−1.6
btag eff. (B 0) - 4.4−4.2 - - - 1.7
−1.7 -
btag eff. (B 1) - 1.6−1.6 - - - - -
JES NP 1 - 1.5−0.2
0.2−0.3
0.1−0.1
0.2−0.2
0.8−0.7
0.2−0.1
JES NP 2 - 0.2−0.0
0.0−0.0
0.0−0.0
0.0−0.0
0.0−0.2
0.0−0.0
JES NP 3 - 0.1−0.0
0.0−0.0
0.0−0.0
0.0−0.0
0.0−0.2
0.0−0.0
JER - 1.9−1.9
0.0−0.0
0.0−0.0
0.2−0.2
0.6−0.6
0.1−0.1
9th May 2016 – 16:38 48
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
TAUS_TRUEHADTAU_SME_TES_TOTAL_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_ggH500W5 BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
TAUS_TRUEHADTAU_SME_TES_TOTAL_1up
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_ggH500W5 BTAG OS
(a)
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
TAUS_TRUEHADTAU_SME_TES_TOTAL_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
TAUS_TRUEHADTAU_SME_TES_TOTAL_1up
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
(b)
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
TAUS_TRUEHADTAU_SME_TES_TOTAL_1down
Nominal (Stat. Unc.)
ATLAS MC Internal Sh_Wtaunu BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
TAUS_TRUEHADTAU_SME_TES_TOTAL_1up
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy_top BTAG OS
(c)
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
TAUS_TRUEHADTAU_SME_TES_TOTAL_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy_top BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
TAUS_TRUEHADTAU_SME_TES_TOTAL_1up
Nominal (Stat. Unc.)
ATLAS MC Internal Sh_Wtaunu BTAG OS
(d)
Figure 33: Ratio of down (left) and up (right) τ energy scale systematic w.r.t nominal in the mTotT distribution for (a)
500 gluon fusion signal and (b) Z → ττ (c) W → τν and (d) Top.
6.3. Uncertainties on data-driven background estimations608
Fake Factor measurement:609
The estimation of the QCD multi-jet background is performed by measuring the TauID fake factor for610
jets in the dijet control region, as described in Section 5. The uncertainty on the fake factor measurement611
is obtained as the sum in quadrature of the statistical uncertainty of the measurement and the difference612
between the fake factor for same-sign and opposite-sign events. The corresponding fake factor measure-613
ment and uncertainties are shown in Table. 10. The effect of the fake factor measurement uncertainty is614
propagated to the QCD background in the statistical analysis.615
Fake rate measurement:616
As the fake rates are determined from data, the main systematic uncertainty comes from the statistical617
9th May 2016 – 16:38 49
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
JET_GroupedNP_1_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
JET_GroupedNP_1_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BVETO OS
(a)
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
JET_GroupedNP_1_1down
Nominal (Stat. Unc.)
ATLAS MC Internal Sh_Wtaunu BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
JET_GroupedNP_1_1down
Nominal (Stat. Unc.)
ATLAS MC Internal Sh_Wtaunu BVETO OS
(b)
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
JET_GroupedNP_1_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy_top BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
JET_GroupedNP_1_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy_top BVETO OS
(c)
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
JET_GroupedNP_1_1down
Nominal (Stat. Unc.)
ATLAS MC Internal Other_BKG BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
JET_GroupedNP_1_1down
Nominal (Stat. Unc.)
ATLAS MC Internal Other_BKG BVETO OS
(d)
Figure 34: Ratio of b-tag (left) and b-veto (right) grouped jet systematic w.r.t the nominal in the mTotT distribution
for (a) Z+τν (b) W+τν (c) Top and (d) Other backgrounds.
uncertainty of the fake rate measurement. The fake rate systematic variation is of ±30%.618
6.4. Uncertainty on W reweighting619
As a systematic uncertainty for the exponential reweighting described in Sec. 5.2.2, the envelope of the620
fit parameter uncertainties are used, i.e. a and b are varied up and down simultaneously. This variation621
results in a significant dependence on mtotT , as shown in Fig 36, and is therefore taken as shape uncertainty622
in the limit fits.623
9th May 2016 – 16:38 50
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
sf_MVX_FT_EFF_Eigen_Light_0_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
sf_MVX_FT_EFF_Eigen_Light_0_1up
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
(a)
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
sf_MVX_FT_EFF_Eigen_B_0_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
sf_MVX_FT_EFF_Eigen_B_0_1up
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
(b)
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
sf_MVX_FT_EFF_Eigen_C_0_1down
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
TAU_TAU_MTOT200 300 400 500 600 700 800 900 1000
Syste
matic / N
om
inal
0
0.5
1
1.5
2
2.5
sf_MVX_FT_EFF_Eigen_C_0_1up
Nominal (Stat. Unc.)
ATLAS MC Internal PoPy8_Ztautau BTAG OS
(c)
Figure 35: Ratio of down (left) and up (right) jet flavour tagging scale factor systematics w.r.t the nominal in themTot
T distribution for (a) light (b) b-jets and (c) c-jets in Z+τν.
Table 10: Fake factor measurement and relative uncertainty for 1-prong and 3-prong events as a function of thesub-leading tau candidate pT.
50-110 GeV 110-160 GeV 160-210 GeV 210-1000 GeV1-prong b-tag 0.11 ± 15% 0.16 ± 12% 0.19 ± 16% 0.20 ± 13%1-prong b-veto 0.077 ± 3.9% 0.120 ± 4.1% 0.151 ± 4.5% 0.174 ± 2.4%3-prong b-tag 0.0051 ± 26% 0.0073 ± 17% 0.0093 ± 32% 0.0107 ± 12%3-prong b-veto 0.0033 ± 6.2% 0.0065 ± 7.0% 0.0076 ± 9.4% 0.0103 ± 8.0%
6.5. Background Cross section uncertainties624
Theoretical cross section uncertainties have been applied to the MC background samples used in this625
analysis. The uncertainties for Z+jets and diboson production are 5% and 6%, respectively, from [79].626
For top pair and single top production the uncertainty is 6% following the twiki recommendations4.627
4 https://twiki.cern.ch/twiki/bin/view/LHCPhysics/SingleTopRefXsec#Predictions_at_7_8_13_and_14_TeV andhttps://twiki.cern.ch/twiki/bin/view/LHCPhysics/TtbarNNLO#Top_quark_pair_cross_sections_at
9th May 2016 – 16:38 51
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
even
ts
1−10
1Nominal
WTAUNUREWEIGHT__1 up
WTAUNUREWEIGHT__1 down = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Nominal
WTAUNUREWEIGHT__1 up
WTAUNUREWEIGHT__1 down = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Nominal
WTAUNUREWEIGHT__1 up
WTAUNUREWEIGHT__1 down = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
totTm
150 200 250 300 350 400 450 500 550 600Rat
io to
Nom
inal
0.60.8
11.21.4
(a) b-tagev
ents
1−10
1
10
Nominal
WTAUNUREWEIGHT__1 up
WTAUNUREWEIGHT__1 down = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS Nominal
WTAUNUREWEIGHT__1 up
WTAUNUREWEIGHT__1 down = 13 TeVs
-1dt L = 3.2 fb∫ InternalATLAS
totTm
200 300 400 500 600 700 800 900 1000Rat
io to
Nom
inal
0.8
1
1.2
(b) b-veto
Figure 36: Impact of W (→ τν)+jets reweighting uncertainty on mtotT distributions in the b-tag and b-veto categories.
6.6. Uncertainties on signal modelling628
Uncertainties related to signal modelling include the uncertainties associated with the initial and final629
state radiation, the modelling of multi-parton interactions, the normalisation and factorisation scale, and630
the parton distribution function.631
To estimate the impact of uncertainties of factorisation and renormalisation scales, these were varied by a632
factor of 2 up and down, including correlated and anti-correlated variations. The results of these variations633
are provided by the respective matrix element generator (aMcAtNlo for the b-associated production signal634
and Powheg for the gluon fusion signal) as vector of weights stored per event in the LHEF event record [80]635
and propagated to the showered samples. A selection close to the full analysis selection was implemented636
at particle level and the change in acceptance due to the differently weighted events was evaluated. The637
largest deviation from the nominal in each direction was taken as final scale uncertainty.638
To estimate the uncertainty due to the parton density function on the gluon fusion signal samples, LHEF639
weights vectors containing a weight for every PDF in PDF4LHC15_nlo_100 [81] are generated and640
variations of acceptance are evaluated like for the variation of the scales. For the b-associated production641
sample the nominal PDF is CT10_nlo_nf4 [82] and since at this time the 4-flavour scheme version of642
the PDF4LHC15 pdfs is not yet available instead the following pdfs are used to model the uncertainty:643
NNPDF30_nlo_as_0118_nf_4 [83], CT14nlo_NF4 [84] andMSTW2008nlo68cl_nf4 [85]. As an estimate644
for the acceptance for these pdfs in the b-associated signal samples the LHAPDF software package [86] was645
utilized to compute event weights. The envelope of the resulting variations in acceptance was chosen as646
combined pdf uncertainty.647
For the estimation of uncertainties arising due to ISR, FSR and MPI modelling, tune variations of the648
Pythia8 A14 tune [87] for the b-associated signal samples and of the AZNLO Pythia8 tune [88] for the649
gluon fusion samples were studied.650
9th May 2016 – 16:38 52
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
variation 400 GeV 700 GeV 1000 GeV
scales +19.2−19.2
+20.3−20.1
+22.3−21.1
PDF +6.0−5.5
+13.1−15.5
+16.2−9.5
tune ±5 ±4 ±3
total (pos.) +20.7 +24.5 +27.7
total (neg.) -20.6 -25.7 - 23.3
Table 11: Signal acceptance uncertainties for b-associated production, b-tag category
variation 400 GeV 700 GeV 1000 GeV
scales +19.3−18.1
+21.4−20.3
+24.4−21.7
PDF +6.5−5.2
+10.5−9.0
+15.1−9.2
tune ±4 ±3 ±3
total (pos.) +20.8 +24.0 +28.9
total (neg.) -19.3 -22.4 - 23.8
Table 12: Signal acceptance uncertainties for b-associated production, b-veto category
variation 400 GeV 700 GeV 1000 GeV
scales +19−15
+19−16
+18−15
PDF ±4.9 ±4.7 ±4.1
tune ±21.3 ±17.4 ±16.1
total (pos.) +29.0 +26.2 +24.5
total (neg.) -26.5 -24.1 -22.4
Table 13: Signal acceptance uncertainties for gluon fusion production in btag category
The uncertainties are summarised in Tables 11, 12 and 13, 14. None of the considered generator parameter651
variations resulted in a statistically significant effect on the shape of the reconstructed mass distribution,652
so all the systematic effects are considered as normalisation uncertainties. In the limit only the combined653
uncertainty per mass point will be considered. The uncertainties for mass points that were not explicitly654
determined and listed here, are interpolated or extrapolated from the others.655
9th May 2016 – 16:38 53
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
variation 400 GeV 700 GeV 1000 GeV
scales +15−13
+15−14
+15−14
PDF ±4.8 ±4.7 ±4.4
tune ±3.1 ±2.6 ±1.2
total (pos.) +16.1 +16.0 +15.7
total (neg.) -14.2 -15.0 -14.7
Table 14: Signal acceptance uncertainties for gluon fusion production in bveto category
category QCD scales Shower generator hard scatter generator combined
b-tag +26.6−17.6 ±4.5 ±26.9 +38.1
−32.5
b-veto +13.3−17.1 ±6.2 ±3.4 +15.0
−18.5
Table 15: The effect on the final event yield of the total top background for the uncertainty arising from the choiceof shower generator and hard scatter generator, given in percent.
6.7. Uncertainties on top modelling656
Uncertainties related to tt modelling include the uncertainties associated with the shower radiation and657
hadronisation model. To estimate the impact of these systematics, the POWHEG+Pythia6 factorisation658
and renormalisation scales are varied by a factor of 2 up and down, and the fragmentation model is659
also compared to the POWHEG+Herwig simulation. Additional uncertainties arising due to the hard scatter660
generation are estimated by comparison of a sample generated by aMcAtNlo and showered usingHerwig++661
to the sample generated by Powheg and showered by Herwig++. tt is the dominant contribution to the662
overall top background in the b-tag category, contributing 89% in total.663
Based on samples available, no statistically significant shape effect is observed for these systematic664
variations, only the effect on the normalisation is considered. The quadratically combined normalisa-665
tion systematic was determined as +15.0−18.5 % in b-veto and +38.1
−32.5 % in the b-tag category. The individual666
components are listed in Table 15.667
7. Z′ → ττ Signal models668
7.1. Signal estimation using Z/γ∗ → Z′ reweighting669
The Z ′ signal templates used in this analysis are obtained by reweighting the simulated Z/γ∗ → ττ sample670
in a similar fashion to what is done in the dilepton analysis [89]. However, a more sophisticated treatment671
is required to correctly account for the polarisation of the tau-leptons, which directly impacts the tau decay672
kinematics. Of most importance is the effect on the neutrino momentum fraction, as this directly impacts673
the reconstructed mtotT .674
9th May 2016 – 16:38 54
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
A very detailed description of the reweighting technique using the TauSpinner algorithm [64] can be found675
in [90]. For completeness the main aspects shall be mentioned again.676
Since version 1.2 of TauSpinner, the algorithm allows reweighting for new resonances, such as Z ′ [91].677
The reweighting relies on information about the spin of the two tau leptons, which is obtained from the678
TauSpinner algorithm. This algorithm allows one to create samples with different tau polarisations from679
an initial sample by re-weighting events. The spin weight is defined as:680
wspin = Ri jhih j , (2)
where Ri j is a matrix describing the full spin correlation between the two taus as well as the individual681
spin states of the taus and hi, h j are the polarimetric vectors of the taus. The weight w used to reweight682
for new resonances is broken into three components: wSMspin, the spin weight for the SM Z/γ∗ process (as683
described above), wBSMspin , the spin weight for the new resonance and wσ , the cross section reweighting684
factor. The latter is defined as the the fraction of squared matrix elements of the new resonance and the685
SM DY process. The full weight to reweight Z/γ∗ events to Z ′ is:686
w =wBSM
spin
wSMspin
wσ =wBSM
spin
wSMspin
MZ′→ττf i
2
MZ/γ∗→ττf i
2 . (3)
The Z ′ decay width is calculated using Pythia8 for each model. In all models interference between Z ′ and687
Z/γ∗ is not included.688
7.2. Sequential Standard Model689
The SSM is utilized as a benchmark model, in various existing analyses, including searches for Z ′ → ``.690
In this model the couplings of the Z ′ are the same as for the SM Z boson.691
The reweighting provided by the TauSpinner algorithm, including the extension to allow reweighting for692
BSM processes, has been extensively validated [64, 90–92]. An additional cross-check to validate the693
reweighting at 13 TeV a simulated Z ′ signal sample is compared to Z/γ∗ → ττ reweighted to a signal694
with the same mass is described in Appendix E.3. Good agreement was found between simulated and695
reweighted signal.696
7.3. Modifications to the Sequential Standard Model697
Changes to the parameter of the Z ′ → ττ can have significant impact on the signal acceptance. In698
particular altering couplings to tau leptons changes polarisation and decay kinematics. This largely699
impacts the visible momentum fraction and this change in turn enters the analysis primarily through the700
pT thresholds of the reconstructed visible tau decay products and via the threshold on mtotT . The tau701
polarisation is most significantly affected by the ratio of the left and right handed coupling strengths of702
the tau-lepton. The polarisation can also be affected, but to a lesser degree, by the ratio of the left and703
right handed coupling strengths of the initial-state quarks.704
The total decay width of the Z ′ is dependent on the couplings to fermions. Naively one would expect705
that since the total decay width for most Z ′ models is much smaller than the experimental ditau mass706
9th May 2016 – 16:38 55
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
resolution, the width would have little impact on the acceptance. This is not true, however, as the width has707
a large impact on the size of the low-mass “parton luminosity” tail (a low mass tail in the true resonance708
mass distribution). In turn, the decay width is a large factors in the Z ′ acceptance.709
A summary of the impact of the couplings on the Z ′ acceptance times efficiency with respect to the710
SSM is given in Fig. 37 for models with altered fermion couplings or decay width. Two models have are711
investigated to cover extreme cases of altered fermion couplings, one which purely couples to left handed712
fermions (g fL = gZ and g
fL = 0), Z ′L, and one that purely couples to right handed fermions (g f
L = 0 and713
gfL = gZ ), Z ′L. For both models the decay width is taken to be the same as for the SSM. The coupling714
definitions have changed with respect to a similar measurement done in Ref. [51] in terms of that in the715
previous study only the couplings to the tau leptons were changed. However, the impact of altered quark716
couplings has already been shown to have less effect on the acceptance than altered couplings to tau717
leptons. The transverse momentum of left handed taus is in general more soft than for right handed taus718
due to their polarisation. Thus the mtotT of Z ′ bosons with purely left handed couplings tend to smaller719
values than the reference of Z ′ bosons in the SSM. On the same note, the opposite is true for Z ′ with720
purely right handed couplings. The impact on the acceptance is largest for small masses due to the pT721
and mtotT thresholds. There the alteration of the couplings leads to changes of up to +67% and −25%.722
With higher mZ′ the impact off the tau kinematics on the acceptance decreases. In the τhadτhad channel723
for mZ′ > 2.2 TeV the total impact of the reconstruction efficiency of the hadronic tau decays at high pT724
is larger than the gain in acceptance.725
Fig. 37 also shows the impact of altered decay widths on the acceptance times efficiency compared to the726
SSM (Γ/mZ′ ≈ 3%). Considered are a model with a narrower decay width Z ′narrow (Γ/mZ′ = 1%) and727
one with a wider decay width of Z ′wide (Γ/mZ′ = 20%). The considered mass range in this study is not as728
sensitive to the large parton luminosity observed in a comparable study done in Ref. [51] due to the higher729
center of mass energy. Therefore the change in acceptance times efficiency is not as large and is found to730
be up to +10% and −25%. An increase in change with increasing mZ′ is observed but is not as prominent731
as in Ref. [51].732
7.4. Strong Flavor Model733
In addition we investigate the presence of possible Z ′ → ττ bosons arise from an additional SU (2)734
gauge group. The so called “Strong Flavour Model” (SFM) is described in [42]. An extremely similar,735
if not identical model called Topflavour was also published around the same time [93]. The models736
were later classified as non-universal types of a more general class of models called G(221) models [94],737
which extend the SM gauge group by adding an additional SU (2) symmetry. Nevertheless, we will stick738
to the name SFM for simplicity’s sake. The authors of the SFM speculate that the large mass of the739
top-quark may suggest a different dynamical behaviour of the third fermion generation from the first two740
generations. They then build a model in which the SM weak SU (2) gauge group is split in two parts: one741
coupling to light fermions (the first two generations), SU (2)l and one coupling to heavy fermions (the742
third generation), SU (2)h. The extended gauge group breaks to the SM SU (2) at some high-energy scale,743
u, and then eventually to U (1)em at the usual electroweak scale, v = 246 GeV. The breaking pattern can744
be written as:745
SU (2)l × SU (2)h ×U (1)Yu→ SU (2)l+h ×U (1)Y
v→ U (1)em (4)
The light fermions have their mass generated via the usual Higgs mechanism, while the heavy fermion746
masses are generated via higher order operators. The model predicts additional weak gauge bosons Z ′ and747
9th May 2016 – 16:38 56
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]Z’
m
500 1000 1500 2000 2500
SS
Mε
A/ε
A
0.6
0.8
1
1.2
1.4
1.6
1.8
2 = 13 TeVs Internal, Simulation, ATLAS
LZ’ RZ’ wideZ’ narrowZ’LZ’ RZ’ wideZ’ narrowZ’
hadτ
hadτ
hadτ
lepτ
Figure 37: Signal acceptance times efficiency for Z ′L, Z ′R, Z ′narrow and Z ′wide divided by the acceptance times efficiencyfor Z ′SSM as a function of m′Z , separately for the τhadτhad, τµτhad and τeτhad channels.
W ′± (which couple preferentially to third generation fermions), altered couplings of the standard model748
weak bosons, and flavour changing neutral currents (FCNCs). Limits on FCNCs in the first two fermion749
generations are extremely strict, so only µ − τ mixing is considered. The model can be described by just750
three additional parameters:751
• sin2 φ: mixing between SU (2)l and SU (2)h. sin2 φ ∼ 0 corresponds to strong coupling of the Z ′ to752
heavy fermions.753
• x: ratio of the SU (2)l/h breaking scale to the electroweak scale, x = u2/v2.754
• sin2 β: µ-τ mixing (sin2 β = 0 corresponds to no mixing and sin2 β = 1 is maximal mixing).755
Limits on the model are derived from fits to electroweak precision data, shown in Figure 38. The limits756
are strongest at high values of sin2 φ, since most of the data involves measurements of the first two fermion757
generations. A lower limit of mZ′ > 1.3 TeV is placed regardless of sin2 φ. More recent indirect limits have758
been calculated in which the authors use an updated set of 37 electroweak precision measurements [95].759
Limits from other authors have also been derived, which use in addition, constraints from CKM unitarity760
9th May 2016 – 16:38 57
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
and lepton flavour violation [96–98]. These limits are shown in Figure 39. The updated limits raise the761
mass exclusion to ∼ 1.8 TeV.762
Figure 38: Limits on the SFM from fits to electroweak precision data [42].
Figure 39: Left: Limits on the SFM (called “Top-Flavour-Doublet model”) from an updated fit of 37 electroweakprecision measurements (green) and from direct searches at the Tevatron (red) and LHC at 7 TeV (blue) [95]. Right:Limits from considering CKM unitarity violation and lepton flavor violation [96].
Fig. 40 (left) shows the ratio of the SFM to SSM cross sections, rσ . For much of the parameter space763
the cross section in the SFM is larger than for the SSM. The cross section of the SFM for values of764
sin2 φ ∼ 1 is suppressed via the decay to tau leptons. The cross section ratio has a peak at moderate765
values of sin2 φ ∼ 0.4. For smaller values the ratio decreases due to a suppression of production via light766
quarks until sin2 φ ∼ 0.1. For even smaller values, the ratio starts increasing steeply as the production via767
b-quarks is getting the dominant production for the SFM. This effect was not properly accounted for in768
the 8 TeV ATLAS Z ′ → ττ search [99], which caused an underestimation of the SFM production cross769
section for small values of sin2 φ.770
Fig. 40 (middle left to right) show the ratios of acceptance times efficiency of the SFM to the SSM for771
9th May 2016 – 16:38 58
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
the τhadτhad, τµτhad and τeτhad channels. In general the acceptance is lower than for the SSM. At low-mass772
this is mainly due to the left-handed couplings, which result in softer visible hadronic tau decays (more773
prominent in the τhadτhad channel). Near sin2 φ ∼ 0 and sin2 φ ∼ 1, the acceptance loss comes mainly774
from the significantly increased decay width, which causes a large fraction of the signal to be produced775
off-shell. The impact from Z ′ interference is expected to be negligible as the couplings are almost purely776
left-handed.777
Figure 40: Signal production cross section times τ+τ− branching fraction for Z ′SFM, σBSFM , divided by σBSFM(left) and acceptance times efficiency for Z ′SFM, AεSFM, divided by AεSSM for the τhadτhad (middle left), τµτhad(middle right) and τeτhad (right) channels, as a function of sin2 φ and m′Z .
8. Results778
8.1. A/H → ττ search779
The parameter of interest in this search is the signal strength, µ, defined as the ratio of the fitted signal780
cross section times branching fraction to the signal cross section times branching fraction predicted by781
the particular MSSM signal assumption. The value µ = 0 corresponds to the absence of signal, whereas782
the value µ = 1 suggests signal presence as predicted by the theoretical model under study. The statistical783
analysis of the data employs a binned likelihood function constructed as the product of Poisson probability784
terms. Signal and background predictions depend on systematic uncertainties, which are parametrised785
as nuisance parameters and are constrained using Gaussian functions. The binned likelihood function is786
constructed in bins of the mtotT mass.787
The final mass discriminant mtotT with post-fit systematic uncertainties for b-tag and b-veto categories are788
shown in Fig. 41. Yields in the signal regions and their uncertainties are summarised in Table 16.789
The data are in good agreement with the predicted background yields and exclusion limits are calculated.790
The significance of any small observed excess in data is evaluated by quoting p-values to quantify the791
level of consistency of the data with the µ = 0 hypothesis. Exclusion limits use the modified frequentist792
method known as CLs [100]. Both the exclusion limits and p-values are calculated using the asymptotic793
approximation [101]. The test statistic used for the exclusion limits derivation is the qµ test statistic and794
9th May 2016 – 16:38 59
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
b-veto
Process Yield uncertaintystat. det. syst. theory syst. total
Multijet 393 5 18 0 19Z/γ∗ → ττ 107 2 29 8 30W → τν 38.7 2.0 7.0 2.7 7.8top, tt 4.0 0.5 1.0 0.7 1.3Others 5.2 0.5 0.9 0.4 1.1Total SM 548 6 34 8 36Data 628 25 0 0 25
b-tag
Process Yield uncertaintystat. det. syst. theory syst. total
Multijet 17.3 1.4 3.0 0.0 3.3Z/γ∗ → ττ 1.42 0.20 0.40 0.10 0.46W → τν 0.90 0.12 0.19 0.06 0.24top, tt 11.4 0.8 2.7 4.1 5.0Others 0.117 0.023 0.027 0.009 0.037Total SM 31.1 1.6 4.0 4.1 6.0Data 23 5 0 0 5
Table 16: Pre-fit signal region yields for data and SM prediction.
for the p-values the q0 test statistic5 [101].795
The limits are interpreted in the MSSM mA − tan β space in the context of the mmod+h
scenario in Fig. 42796
and are compared to the previous result. In Fig. 43 the limits of the individual categories are shown.797
The systematics used for the limit reflect the uncertainties values discussed in Section 6. In Figure 44798
the impact of the systematic uncertainties on the fitted signal strength and variations of the nuisance799
parameters from their nominal values in units of their uncertainty values is shown for mA/H = 300 GeV,800
500 GeV and 1000 GeV. Similar plots for separate b-tag and b-veto categories are listed in Appendix B801
in Figures 54-55.802
Validity checks of the asymptotic approximation have been performed and are shown in Appendix C. The803
result presented here sets the strongest limit so far in the high-mA region of the MSSM parameter space.804
5 The definition of the test statistics used in this search is the following:
qµ =
−2 ln(L(µ, ˆθ)/L(0, ˆθ)) if µ < 0−2 ln(L(µ, ˆθ)/L( µ, θ)) if 0 ≤ µ ≤ µ
0 if µ > µ
and
q0 =−2 ln(L(0, ˆθ)/L( µ, θ)) if µ ≥ 00 if µ < 0
where L(µ, θ) denotes the binned likelihood function, µ is the parameter of interest (i.e. the signal strength parameter), andθ denotes the nuisance parameters. The pair ( µ, θ) corresponds to the global maximum of the likelihood, whereas (x, ˆθ)corresponds to a conditional maximum in which µ is fixed to a given value x.
9th May 2016 – 16:38 60
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Eve
nts
/ G
eV
4−10
3−10
2−10
1−10
1
10
210
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
[GeV]totTm
200 300 400 500 600 700 800 900 1000Da
ta/P
red
.
00.5
11.5
2
(a) b-veto category
Eve
nts
/ G
eV
0
0.05
0.1
0.15
0.2
0.25
0.3
0.35Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
[GeV]totTm
150 200 250 300 350 400 450 500 550 600Da
ta/P
red
.
0.5
1
1.5
(b) b-tag category
Figure 41: Distribution of final mass discriminant mtotT with post-fit uncertainties. The binning shown corresponds
to the one used for the fit.
A combination with the τlepτhad channel has been performed to improve the overall sensitivity. The results805
of the combination are shown in the supporting document for the τlepτhad analysis [102].806
9th May 2016 – 16:38 61
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
mA [GeV]200 400 600 800 1000 1200
βta
n
15
20
25
30
35
40
45
50
55
60combined - observedcombined - expected
σ 1±combined - σ 2±combined -
b-tag - expectedb-veto - expectedhh EOYE - expected
combined - observedcombined - expected
σ 1±combined - σ 2±combined -
b-tag - expectedb-veto - expectedhh EOYE - expected
combined - observedcombined - expected
σ 1±combined - σ 2±combined -
b-tag - expectedb-veto - expectedhh EOYE - expected
combined - observedcombined - expected
σ 1±combined - σ 2±combined -
b-tag - expectedb-veto - expectedhh EOYE - expected
-1 = 13 TeV, 3.2 fbs > 0µ, mod+
h, mhadτ hadτ →A/H
95% CL
Figure 42: The 95% CL upper limit on the mA–tan β plane of the MSSM parameter space in the mmod+h
scenario for3.21 fb−1of integrated luminosity at 13 TeV. In addition, the previous sensitivity from ATLAS-CONF-2015-061 isshown.
9th May 2016 – 16:38 62
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
mA [GeV]200 400 600 800 1000 1200
βta
n
15
20
25
30
35
40
45
50
55
60
b-veto - observedb-veto - expected
σ 1±b-veto - σ 2±b-veto -
hh EOYE - expected
b-veto - observedb-veto - expected
σ 1±b-veto - σ 2±b-veto -
hh EOYE - expected
-1 = 13 TeV, 3.2 fbs > 0µ, mod+
h, mhadτ hadτ →A/H
95% CL
(a) b-veto category
mA [GeV]200 400 600 800 1000 1200
βta
n
15
20
25
30
35
40
45
50
55
60
b-tag - observedb-tag - expected
σ 1±b-tag - σ 2±b-tag -
hh EOYE - expected
b-tag - observedb-tag - expected
σ 1±b-tag - σ 2±b-tag -
hh EOYE - expected
-1 = 13 TeV, 3.2 fbs > 0µ, mod+
h, mhadτ hadτ →A/H
95% CL
(b) b-tag category
Figure 43: The 95% CL upper limit on the mA–tan β plane of the MSSM parameter space in the mmod+h
scenario for3.21 fb−1of integrated luminosity at 13 TeV.
2− 1− 0 1 2
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_btagEffSfEigen_B_1
alpha_ATLAS_btagEffSfEigen_C_1
alpha_ATLAS_btagEffSfEigen_C_0
alpha_ATLAS_JETNP3
alpha_ATLAS_btagEffSfEigen_Light_0
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_TES_AF2
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_AU_ggH_MA300
alpha_ATLAS_JERNP1
alpha_ATLAS_TES_MODEL
alpha_ATLAS_PRW
alpha_ATLAS_xsec_Top
alpha_ATLAS_xsec_Z
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_TAURECO
alpha_ATLAS_JVT
alpha_ATLAS_JETNP1
alpha_ATLAS_TES_INSITU
alpha_ATLAS_AU_bbH_MA300
alpha_ATLAS_LUMI
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_TAUID
alpha_ATLAS_TAUTRIG
alpha_ATLAS_TTBAR_NORM
alpha_ATLAS_HADHAD_FF
µ∆
0.15− 0.1− 0.05− 0 0.05 0.1 0.15
θ∆)/0θ - θ(1.5− 1− 0.5− 0 0.5 1 1.5
1 standard deviation
µPrefit Impact on
µPostfit Impact on =15β=300 GeV, tanAm
(a)
2− 1.5− 1− 0.5− 0 0.5 1 1.5 2
alpha_ATLAS_btagEffSfEigen_B_1
alpha_ATLAS_JETNP3
alpha_ATLAS_btagEffSfEigen_Light_1
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_AU_ggH_MA500
alpha_ATLAS_JETNP1
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_JERNP1
alpha_ATLAS_btagEffSfEigen_C_1
alpha_ATLAS_btagEffSfEigen_C_0
alpha_ATLAS_TES_MODEL
alpha_ATLAS_btagEffSfEigen_Light_0
alpha_ATLAS_PRW
alpha_ATLAS_TAURECO
alpha_ATLAS_JVT
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_LUMI
alpha_ATLAS_xsec_Z
alpha_ATLAS_xsec_Top
alpha_ATLAS_TAUTRIG
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_HADHAD_FF
alpha_ATLAS_TAUID
alpha_ATLAS_TES_INSITU
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_AU_bbH_MA500
alpha_ATLAS_TTBAR_NORM
µ∆
0.2− 0.15− 0.1− 0.05− 0 0.05 0.1 0.15 0.2
θ∆)/0θ - θ(1− 0.5− 0 0.5 1
1 standard deviation
µPrefit Impact on
µPostfit Impact on =20β=500 GeV, tanAm
(b)
8− 6− 4− 2− 0 2 4 6 8
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_btagEffSfEigen_C_1
alpha_ATLAS_TAURECO_HIGHPT
alpha_ATLAS_btagEffSfEigen_Light_2
alpha_ATLAS_JETNP2
alpha_ATLAS_JETNP3
alpha_ATLAS_AU_ggH_MA1000
alpha_ATLAS_JERNP1
alpha_ATLAS_btagEffSfEigen_B_1
alpha_ATLAS_JETNP1
alpha_ATLAS_PRW
alpha_ATLAS_btagEffSfEigen_C_0
alpha_ATLAS_btagEffSfEigen_Light_0
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_TES_MODEL
alpha_ATLAS_xsec_Z
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_TAURECO
alpha_ATLAS_TES_INSITU
alpha_ATLAS_LUMI
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_JVT
alpha_ATLAS_xsec_Top
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_TAUID
alpha_ATLAS_HADHAD_FF
alpha_ATLAS_AU_bbH_MA1000
alpha_ATLAS_TAUTRIG
alpha_ATLAS_TTBAR_NORM
µ∆
0.06− 0.04− 0.02− 0 0.02 0.04 0.06
θ∆)/0θ - θ(2− 1.5− 1− 0.5− 0 0.5 1 1.5 2
1 standard deviation
µPrefit Impact on
µPostfit Impact on =50β=1000 GeV, tanAm
(c)
Figure 44: Impact of the systematic uncertainties on the fitted signal strength and variations of the nuisance parametersfrom their nominal values in units of their uncertainty values for mA/H = 300 GeV, 500 GeV and 1000 GeV. Thevalues of tan β correspond to the mmod+
hscenario and are chosen to be close to the expected limit.
9th May 2016 – 16:38 63
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
mtotT cut Signal Z/γ∗ → ττ QCD W → τν Top Others Data
400 GeV mZ′ = 0.50TeV 14.7 ± 5.2 8.7 ± 1.2 4.5 ± 0.9 1.6 ± 1.5 1.0 ± 0.3 29 ± 5.4373.1 ± 139.2
400 GeV mZ′ = 0.60TeV 14.7 ± 5.2 8.7 ± 1.2 4.5 ± 0.9 1.6 ± 1.5 1.0 ± 0.3 29 ± 5.4349.6 ± 114.8
400 GeV mZ′ = 0.70TeV 14.7 ± 5.2 8.7 ± 1.2 4.5 ± 0.9 1.6 ± 1.5 1.0 ± 0.3 29 ± 5.4269.1 ± 86.2
450 GeV mZ′ = 0.80TeV 9.4 ± 3.3 3.8 ± 0.8 2.7 ± 0.6 0.8 ± 1.2 0.8 ± 0.2 17 ± 4.1164.2 ± 53.2
500 GeV mZ′ = 0.90TeV 6.2 ± 2.2 1.7 ± 0.6 1.7 ± 0.4 0.4 ± 1.3 0.6 ± 0.2 11 ± 3.3100.4 ± 33.1
550 GeV mZ′ = 1.00TeV 3.9 ± 1.5 1.1 ± 0.4 1.0 ± 0.2 0.2 ± 0.6 0.4 ± 0.2 6 ± 2.464.9 ± 21.7
650 GeV mZ′ = 1.25TeV 1.9 ± 0.7 0.4 ± 0.3 0.4 ± 0.1 0.0 ± 0.0 0.2 ± 0.1 2 ± 1.424.5 ± 8.4
750 GeV mZ′ = 1.50TeV 0.9 ± 0.4 0.0 ± 0.1 0.2 ± 0.0 0.0 ± 0.0 0.2 ± 0.1 1 ± 1.09.8 ± 3.5
750 GeV mZ′ = 1.75TeV 0.9 ± 0.4 0.0 ± 0.1 0.2 ± 0.0 0.0 ± 0.0 0.2 ± 0.1 1 ± 1.04.7 ± 1.7
750 GeV mZ′ = 2.00TeV 0.9 ± 0.4 0.0 ± 0.1 0.2 ± 0.0 0.0 ± 0.0 0.2 ± 0.1 1 ± 1.02.4 ± 0.9
750 GeV mZ′ = 2.25TeV 0.9 ± 0.4 0.0 ± 0.1 0.2 ± 0.0 0.0 ± 0.0 0.2 ± 0.1 1 ± 1.01.2 ± 0.4
750 GeV mZ′ = 2.50TeV 0.9 ± 0.4 0.0 ± 0.1 0.2 ± 0.0 0.0 ± 0.0 0.2 ± 0.1 1 ± 1.00.6 ± 0.2
Table 17: Signal region yields for Z ′ → ττ signal and SM prediction for various cuts on mtotT . Event yields for the
different masses of the signal model are only given for the threshold used to define the final mass window. Thetotal uncertainty includes besides the statistical and systematical uncertainties from detector-related sources also theuncertainty on the luminosity (5%) and, where applicable, the uncertainty of the calculated cross section (5-6%).
8.2. Z′ → ττ search807
The event yields in the final mass windows for all mass hypotheses for the Z ′ → ττ in the SSM are808
summarised in Table 17.809
For the statistical analysis a likelihood fit is utilised. The limits are interpreted in the SSM in Fig. 45. The810
systematics used for the limit reflect the uncertainties values discussed in Section 6. The resulting 95 %811
CL observed and expected lower limits on the mass of a Z ′SSM are 1.77 TeV and 1.73 TeV, respectively. The812
observed limit is not reaching the corresponding already set lower mass limit on Z ′SSM of 1.89 TeV [51] in813
the τhadτhad channel, but it is competitive. In Figure 46 the impact of the systematic uncertainties on the814
fitted signal strength and variations of the nuisance parameters from their nominal values in units of their815
uncertainty values is shown for mZ′ = 100 GeV, 1500 GeV and 2000 GeV.816
9th May 2016 – 16:38 64
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]Z’m
500 1000 1500 2000 2500
) [p
b]
ττ
→Z
’(
B ×
+ X
) Z
’→
pp
(σ
2−10
1−10
1
10
210
310σ 2±Expected Limit
σ 1±Expected Limit
Expected Limit
Observed Limit
SSMZ’ channelhad
τhad
τ = 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS σ 2±Expected Limit
σ 1±Expected Limit
Expected Limit
Observed Limit
SSMZ’ channelhad
τhad
τ = 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS σ 2±Expected Limit
σ 1±Expected Limit
Expected Limit
Observed Limit
SSMZ’ channelhad
τhad
τ = 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS σ 2±Expected Limit
σ 1±Expected Limit
Expected Limit
Observed Limit
SSMZ’ channelhad
τhad
τ = 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS
Figure 45: The 95 % CL upper limit on the cross section times ditau branching fraction for a Z ′ → ττ in theSequential Standard Model in the τhadτhad channel including the 1σ and 2σ uncertainty bands for 3.21 fb−1 ofintegrated luminosity at 13 TeV. The observed and expected lower limits on the mass of a Z ′SSM are 1.77 TeV and1.73 TeV, respectively.
8.3. Combination of τ`τhad and τhadτhad channels for the Z′ → ττ search817
A combination of all channels, τhadτhad, τµτhad and τeτhad, is performed for the Z ′SSM interpretation.818
The resulting upper limits on the cross section times ditau branching fraction are shown in Figure 47.819
A breakdown of contributions to the combined limit of the individual τhadτhad and τ τhad is shown in820
Figure 48.821
The resulting 95% CL observed (expected) lower limits on the mass of a Z ′SSM are 1.90 TeV (1.84 TeV).822
The observed limit is not reaching the highest existing lower mass limit on Z ′SSM of 2.02 TeV [51] for823
the same channel combination, but they are competitive. Table 18 summarises all lower limits set on the824
Z ′SSM mass.825
Limits on the Strong Flavor model are also calculated. The signal contributions in the τhadτhad, τµτhad and826
τeτhad channels are rescaled by σBSFM/σBSSM · AεSFM/AεSSM (as derived in Section 7.4). In addition,827
the systematic uncertainties are re-evaluated for each point in parameter space. Figure 49 shows the region828
in the Z ′SFM parameter space excluded at 95% CL: Z ′SFM bosons with masses below 1.82–2.18 TeV are829
9th May 2016 – 16:38 65
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
2− 1− 0 1 2
alpha_ATLAS_JETNP1
alpha_ATLAS_TES_MODEL
alpha_ATLAS_HADHAD_QCDFF
alpha_ATLAS_JETNP2
alpha_ATLAS_LPX_KFACTOR_SCALE_Z
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_xsec_Top
alpha_ATLAS_JETNP3
alpha_ATLAS_JET_EtaIntercalibration_NonClosure
alpha_ATLAS_TAURECOHIGHPT
alpha_ATLAS_LPX_KFACTOR_PI
alpha_ATLAS_HADHAD_FAKERATE
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_TAURECO
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_LPX_KFACTOR_PDF
alpha_ATLAS_LUMI
alpha_ATLAS_xsec_Z
alpha_ATLAS_TAUIDHIGHPT
alpha_ATLAS_PRW
alpha_ATLAS_TES_INSITU
alpha_ATLAS_TTBAR_RAD
alpha_ATLAS_TAUID
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_TAUTRIGGER
µ∆
0.04− 0.03− 0.02− 0.01− 0 0.01 0.02 0.03 0.04
θ∆)/0
θ θ(
2− 1− 0 1 2
1 standard deviation
µPrefit Impact on
µPostfit Impact on = 1000 GeVZ’
m
(a)
4− 2− 0 2 4
alpha_ATLAS_TES_MODEL
alpha_ATLAS_TAURECOHIGHPT
alpha_ATLAS_LPX_KFACTOR_SCALE_Z
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_JET_EtaIntercalibration_NonClosure
alpha_ATLAS_HADHAD_QCDFF
alpha_ATLAS_xsec_Top
alpha_ATLAS_JETNP2
alpha_ATLAS_JETNP3
alpha_ATLAS_LPX_KFACTOR_PI
alpha_ATLAS_JETNP1
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_TAURECO
alpha_ATLAS_TTBAR_RAD
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_HADHAD_FAKERATE
alpha_ATLAS_LUMI
alpha_ATLAS_LPX_KFACTOR_PDF
alpha_ATLAS_xsec_Z
alpha_ATLAS_PRW
alpha_ATLAS_TAUIDHIGHPT
alpha_ATLAS_TES_INSITU
alpha_ATLAS_TAUID
alpha_ATLAS_TAUTRIGGER
alpha_ATLAS_TES_DETECTOR
µ∆
0.1− 0.05− 0 0.05 0.1
θ∆)/0
θ θ(
4− 2− 0 2 4
1 standard deviation
µPrefit Impact on
µPostfit Impact on = 1500 GeVZ’
m
(b)
4− 3− 2− 1− 0 1 2 3 4
alpha_ATLAS_xsec_Top
alpha_ATLAS_JET_EtaIntercalibration_NonClosure
alpha_ATLAS_HADHAD_QCDFF
alpha_ATLAS_JETNP2
alpha_ATLAS_JETNP3
alpha_ATLAS_LPX_KFACTOR_SCALE_Z
alpha_ATLAS_JETNP1
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_TES_MODEL
alpha_ATLAS_TAURECOHIGHPT
alpha_ATLAS_TTBAR_RAD
alpha_ATLAS_LPX_KFACTOR_PI
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_TAURECO
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_HADHAD_FAKERATE
alpha_ATLAS_LUMI
alpha_ATLAS_LPX_KFACTOR_PDF
alpha_ATLAS_xsec_Z
alpha_ATLAS_TAUIDHIGHPT
alpha_ATLAS_PRW
alpha_ATLAS_TES_INSITU
alpha_ATLAS_TAUID
alpha_ATLAS_TAUTRIGGER
alpha_ATLAS_TES_DETECTOR
µ∆
0.4− 0.3− 0.2− 0.1− 0 0.1 0.2 0.3 0.4
θ∆)/0
θ θ(
4− 3− 2− 1− 0 1 2 3 4
1 standard deviation
µPrefit Impact on
µPostfit Impact on = 2000 GeVZ’
m
(c)
Figure 46: Impact of the systematic uncertainties on the fitted signal strength and variations of the nuisance parametersfrom their nominal values in units of their uncertainty values for mZ′ = 1000 GeV, 1500 GeV and 2000 GeV.
lower limit on mZ′ in the SSMchannel observed [TeV] expected [TeV]τeτhad 1.49 1.47τµτhad 1.55 1.52τ τhad 1.68 1.64τhadτhad 1.77 1.73combined 1.90 1.84
Table 18: Summary of observed and expected lower limits on the mass of a Z ′ in the SSM for the individual channelsand their combination.
excluded in the range 0.1 < sin2 φ < 0.5 assuming no µ− τ mixing. For the smallest value of sin2 φ under830
investigation the limit lower limit on the mass of a Z ′SFM is 2.11 TeV, which exceeds all previous direct831
and indirect searches by more than 300 GeV.832
9th May 2016 – 16:38 66
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]Z’m
500 1000 1500 2000 2500
) [p
b]
ττ
→Z
’(
B ×
+ X
) Z
’→
pp
(σ
2−10
1−10
1
10
σ 2±Expected Limit
σ 1±Expected Limit
Expected Limit
Observed Limit
SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS σ 2±Expected Limit
σ 1±Expected Limit
Expected Limit
Observed Limit
SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS σ 2±Expected Limit
σ 1±Expected Limit
Expected Limit
Observed Limit
SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS
Figure 47: The 95% CL upper limit on the cross section times ditau branching fraction for a Z ′ → ττ in theSequential Standard Model for the combination of the τhadτhad, τµτhad and τeτhad channels including the 1σ and 2σuncertainty bands for 3.21 fb−1 of integrated luminosity at 13 TeV. The observed (expected) lower limits on themass of a Z ′SSM are 1.90 TeV (1.84 TeV).
9th May 2016 – 16:38 67
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[GeV]Z’m
500 1000 1500 2000 2500
) [p
b]
ττ
→Z
’(
B ×
+ X
) Z
’→
pp
(σ
2−10
1−10
1
10Observed Limit all Expected Limit all
Observed Limit hadhad Expected Limit hadhad
Observed Limit lephad Expected Limit lephad
SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS
Observed Limit all Expected Limit all
Observed Limit hadhad Expected Limit hadhad
Observed Limit lephad Expected Limit lephad
SSMZ’
= 13 TeVs
1dt L = 3.2 fb∫ InternalATLAS
Figure 48: The 95% CL upper limit on the cross section times ditau branching fraction for a Z ′ → ττ in theSequential Standard Model for the τhadτhad and τ τhad channels and their combination for 3.21 fb−1 of integratedluminosity at 13 TeV.
9th May 2016 – 16:38 68
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
φ2sin
0.1 0.2 0.3 0.4 0.5
[G
eV
]Z
’m
500
1000
1500
2000
2500
3000
3500 (13 TeV)ττ→Z’ATLAS
(8 TeV)ττ→Z’ATLAS
Indirect (EWPT)
Indirect (LFV)
Indirect (CKM)
pole)ZIndirect (
1dt L = 3.2 fb∫
InternalATLAS (13 TeV)ττ→Z’ATLAS
(8 TeV)ττ→Z’ATLAS
Indirect (EWPT)
Indirect (LFV)
Indirect (CKM)
pole)ZIndirect (
1dt L = 3.2 fb∫
InternalATLAS (13 TeV)ττ→Z’ATLAS
(8 TeV)ττ→Z’ATLAS
Indirect (EWPT)
Indirect (LFV)
Indirect (CKM)
pole)ZIndirect (
1dt L = 3.2 fb∫
InternalATLAS
Figure 49: Observed 95% CL exclusion on the SFM parameter space from the combination of the τhadτhad, τµτhadand τeτhad channels channels (blue). Direct limits from the ATLAS Z ′ → ττ 8TeV search[99] and indirect limits at95% CL from fits to electroweak precision measurements (EWPT)[95], lepton flavour violation (LFV)[98], CKMunitarity[97] and the original Z-pole data[42] are overlaid.
9th May 2016 – 16:38 69
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
9. Conclusions833
A search for a heavy ττ resonances with the ATLAS detector at the LHC using 13 TeV data was presented834
in this note. Event distributions are shown based on simulated samples from the MC15 25 ns campaign835
and 13 TeV data that correspond to 3.21 fb−1.836
No excess is found in data with respect to the predicted background yields and exclusion limits are837
calculated. The interpretation of the Higgs result is performed in form of the limit in the MSSM838
mA − tan β parameter space. Upper limits on σ(pp → Z ′ + X ) × B(Z ′ → ττ) and lower limits on the839
mass of a Z ′ are set in the Sequential Standard Model.840
References841
[1] ATLAS Collaboration, Observation of a new particle in the search for the Standard Model Higgs842
boson with the ATLAS detector at the LHC, Phys. Lett. B 716 (2012) 1–29,843
arXiv: 1207.7214 [hep-ex].844
[2] CMS Collaboration,845
Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC,846
Phys. Lett. B 716 (2012) 30–61, arXiv: 1207.7235 [hep-ex].847
[3] ATLAS Collaboration, Measurements of Higgs boson production and couplings in diboson final848
states with the ATLAS detector at the LHC, Phys. Lett. B 726 (2013) 88–119,849
arXiv: 1307.1427 [hep-ex].850
[4] ATLAS Collaboration, Evidence for the spin-0 nature of the Higgs boson using ATLAS data,851
Phys. Lett. B 726 (2013) 120–144, arXiv: 1307.1432 [hep-ex].852
[5] CMS Collaboration, Evidence for the direct decay of the 125 GeV Higgs boson to fermions,853
Nature Phys. 10 (2014), arXiv: 1401.6527 [hep-ex].854
[6] CMS Collaboration,855
Measurement of the properties of a Higgs boson in the four-lepton final state,856
Phys.Rev. D 89 (2014) 092007, arXiv: 1312.5353 [hep-ex].857
[7] CMS Collaboration, Measurement of Higgs boson production and properties in the WW decay858
channel with leptonic final states, JHEP 01 (2014) 096, arXiv: 1312.1129 [hep-ex].859
[8] F. Englert and R. Brout, Broken symmetry and the mass of gauge vector mesons,860
Phys. Rev. Lett. 13 (1964) 321–323.861
[9] P. W. Higgs, Broken symmetries, massless particles and gauge fields,862
Phys. Lett. 12 (1964) 132–133.863
[10] P. W. Higgs, Broken symmetries and the masses of gauge bosons,864
Phys. Rev. Lett. 13 (1964) 508–509.865
[11] P. W. Higgs, Spontaneous symmetry breakdown without massless bosons,866
Phys. Rev. 145 (1966) 1156–1163.867
[12] G. Guralnik, C. Hagen and T. Kibble, Global conservation laws and massless particles,868
Phys. Rev. Lett. 13 (1964) 585–587.869
[13] T. Kibble, Symmetry breaking in non-Abelian gauge theories, Phys. Rev. 155 (1967) 1554–1561.870
9th May 2016 – 16:38 70
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[14] A. Djouadi, The Anatomy of electro-weak symmetry breaking. II. The Higgs bosons in the871
minimal supersymmetric model, Phys. Rept. 459 (2008) 1–241,872
arXiv: hep-ph/0503173 [hep-ph].873
[15] G. Branco et al., Theory and phenomenology of two-Higgs-doublet models,874
Phys. Rept. 516 (2012) 1–102, arXiv: 1106.0034 [hep-ph].875
[16] P. Fayet, Supersymmetry and Weak, Electromagnetic and Strong Interactions,876
Phys. Lett. B 64 (1976) 159.877
[17] P. Fayet, Spontaneously Broken Supersymmetric Theories of Weak, Electromagnetic and Strong878
Interactions, Phys. Lett. B 69 (1977) 489.879
[18] G. R. Farrar and P. Fayet, Phenomenology of the Production, Decay, and Detection of New880
Hadronic States Associated with Supersymmetry, Phys. Lett. B 76 (1978) 575–579.881
[19] P. Fayet, Relations Between the Masses of the Superpartners of Leptons and Quarks, the882
Goldstino Couplings and the Neutral Currents, Phys. Lett. B 84 (1979) 416.883
[20] S. Dimopoulos and H. Georgi, Softly Broken Supersymmetry and SU(5),884
Nucl. Phys. B 193 (1981) 150.885
[21] S. Heinemeyer, W. Hollik and G. Weiglein, Constraints on tan Beta in the MSSM from the upper886
bound on the mass of the lightest Higgs boson, JHEP 06 (2000) 009,887
arXiv: hep-ph/9909540 [hep-ph].888
[22] M. Carena, S. Heinemeyer, C. E. M. Wagner and G. Weiglein,889
Suggestions for benchmark scenarios for MSSM Higgs boson searches at hadron colliders,890
Eur. Phys. J. C 26 (2003) 601, arXiv: hep-ph/0202167 [hep-ph].891
[23] M. Carena et al., MSSM Higgs Boson Searches at the LHC: Benchmark Scenarios after the892
Discovery of a Higgs-like Particle, Eur. Phys. J. C 73 (2013) 2552,893
arXiv: 1302.7033 [hep-ph].894
[24] ATLAS Collaboration, Measurement of the Higgs boson mass from the H → γγ and895
H → Z Z∗ → 4` channels with the ATLAS detector using 25 fb−1 of pp collision data,896
Phys. Rev. D90.5 (2014) 052004, arXiv: 1406.3827 [hep-ex].897
[25] P. Bechtle et al., MSSM Interpretations of the LHC Discovery: Light or Heavy Higgs?,898
Eur. Phys. J. C 73 (2013) 2354, arXiv: 1211.1955 [hep-ph].899
[26] A. Arbey et al.,900
The Higgs sector of the phenomenological MSSM in the light of the Higgs boson discovery,901
JHEP 09 (2012) 107, arXiv: 1207.1348 [hep-ph].902
[27] DELPHI, OPAL, ALEPH, LEP Working Group for Higgs Boson Searches, L3,903
Search for neutral MSSM Higgs bosons at LEP, Eur. Phys. J. C47 (2006) 547–587,904
arXiv: hep-ex/0602042 [hep-ex].905
[28] T. N. P. . H. W. Group, Combined CDF and D0 Upper Limits on MSSM Higgs Boson Production906
in tau-tau Final States with up to 2.2 fb-1 (2010), arXiv: 1003.3363 [hep-ex].907
[29] CDF Collaboration, T. Aaltonen et al., Search for Higgs bosons predicted in two-Higgs-doublet908
models via decays to τ lepton pairs in 1.96 TeV proton–antiproton collisions,909
Phys. Rev. Lett. 103 (2009) 201801, arXiv: 0906.1014 [hep-ex].910
9th May 2016 – 16:38 71
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[30] D0 Collaboration, V. M. Abazov et al.,911
Search for Higgs bosons decaying to τ pairs in pp collisions with the D0 detector,912
Phys. Rev. Lett. 101 (2008) 071804, arXiv: 0805.2491 [hep-ex].913
[31] ATLAS Collaboration, Search for neutral Higgs bosons of the minimal supersymmetric standard914
model in pp collisions at√
s = 8 TeV with the ATLAS detector, JHEP 1411 (2014) 056,915
arXiv: 1409.6064 [hep-ex].916
[32] ATLAS Collaboration, Search for the neutral Higgs bosons of the minimal supersymmetric917
standard model in pp collisions at√
s = 7 TeV with the ATLAS detector, JHEP 02 (2013) 095,918
arXiv: 1211.6956 [hep-ex].919
[33] CMS Collaboration,920
Search for neutral MSSM Higgs bosons decaying to a pair of tau leptons in pp collisions,921
JHEP 10 (2014) 160, arXiv: 1408.3316 [hep-ex].922
[34] LHCb Collaboration, R. Aaij et al.,923
Limits on neutral Higgs boson production in the forward region in pp collisions at√
s = 7 TeV,924
JHEP 05 (2013) 132, arXiv: 1304.2591 [hep-ex].925
[35] J. L. Hewett and T. G. Rizzo, Low-energy phenomenology of superstring-inspired E6 models,926
Phys. Rept. 183 (1989) 193–381.927
[36] M. Cvetic and S. Godfrey, Discovery and identification of extra gauge bosons (1995),928
arXiv: hep-ph/9504216.929
[37] A. Leike, The Phenomenology of extra neutral gauge bosons, Phys. Rept. 317 (1999) 143–250,930
arXiv: hep-ph/9805494.931
[38] T. G. Rizzo, Z ′ phenomenology and the LHC932
(2006) 537–575, Published in Boulder, 2006, Colliders and Neutrinos (TASI 2006),933
arXiv: hep-ph/0610104.934
[39] R. Diener, S. Godfrey and T. A. Martin,935
Unravelling an Extra Neutral Gauge Boson at the LHC using Third Generation Fermions,936
83 (2011) 115008, arXiv: 1006.2845 [hep-ph].937
[40] P. Langacker, The Physics of Heavy Z ′ Gauge Bosons, 81 (2009) 1199–1228,938
arXiv: 0801.1345 [hep-ph].939
[41] K. R. Lynch et al.,940
Finding Z ′ bosons coupled preferentially to the third family at LEP and the Tevatron,941
63 (2001) 035006, arXiv: hep-ph/0007286.942
[42] E. Malkawi, T. Tait and C.-P. Yuan, A model of strong flavor dynamics for the top quark,943
385 (1996) 304–310, arXiv: hep-ph/9603349.944
[43] H. D. Kim, S.-G. Kim and S. Shin,945
D0 dimuon charge asymmetry from Bs system with Z′ couplings and the recent LHCb result,946
88, 015005 (2013) 015005, arXiv: 1205.6481 [hep-ph].947
[44] X.-G. He and G. Valencia, B decays with τ leptons in nonuniversal left-right models,948
87, 014014 (2013) 014014, arXiv: 1211.0348 [hep-ph].949
[45] E. Dudas, C. Petersson and R. Torre,950
Collider signatures of low scale supersymmetry breaking: A Snowmass 2013 White Paper (),951
arXiv: 1309.1179 [hep-ph].952
9th May 2016 – 16:38 72
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[46] C. Petersson, A. Romagnoni and R. Torre, Liberating Higgs couplings in supersymmetry,953
87, 013008 (2013) 013008, arXiv: 1211.2114 [hep-ph].954
[47] V. Barger, D. Marfatia and A. Peterson, LHC and dark matter signals of Z′ bosons,955
87, 015026 (2013) 015026, arXiv: 1206.6649 [hep-ph].956
[48] A. Hayreter and G. Valencia,957
Constraining τ-lepton dipole moments and gluon couplings at the LHC,958
88, 013015 (2013) 013015, arXiv: 1305.6833 [hep-ph].959
[49] ATLAS Collaboration, A search for high-mass resonances decaying to tau+tau- in pp collisions960
at sqrt(s) = 7 TeV with the ATLAS detector, 719 (2013) 242 –260, arXiv: 1210.6604 [hep-ex].961
[50] CMS Collaboration, Search for high-mass resonances decaying into tau-lepton pairs in pp962
collisions at sqrt(s) = 7 TeV, 716 (2012) 82 –102, arXiv: 1206.1725 [hep-ex].963
[51] ATLAS Collaboration, A search for high-mass resonances decaying to τ+τ− in pp collisions at964√
s = 8 TeV with the ATLAS detector, J. High Energy Phys. 07 (2015), arXiv: 1502.07177.965
[52] R. S. Chivukula and E. H. Simmons, Electroweak limits on nonuniversal Z ′ bosons,966
66 (1 2002) 015006, arXiv: hep-ph/0205064.967
[53] Search for high-mass dilepton resonances in pp collisions at√
s = 8 TeV with the ATLAS968
detector, submitted to Phys. Rev. D (2014), arXiv: 1405.4123 [hep-ex].969
[54] Search for Resonances in the Dilepton Mass Distribution in pp Collisions at√
s = 8 TeV,970
CMS-PAS-EXO-12-061 ().971
[55] ATLAS Collaboration, The ATLAS experiment at the CERN Large Hadron Collider,972
JINST 3 (2008) S08003.973
[56] ATLAS Collaboration, The ATLAS simulation infrastructure, Eur. Phys. J. C 70 (2010) 823–874,974
arXiv: 1005.4568 [physics.ins-det].975
[57] T. Gleisberg et al., Event generation with SHERPA 1.1, JHEP 02 (2009) 007,976
arXiv: 0811.4622 [hep-ph].977
[58] S. Alioli et al.,978
NLO Higgs boson production via gluon fusion matched with shower in POWHEG,979
JHEP 04 (2009) 002, arXiv: 0812.0578 [hep-ph].980
[59] T. Sjöstrand, S. Mrenna and P. Skands, PYTHIA 6.4 physics and manual, JHEP 05 (2006) 026,981
arXiv: hep-ph/0603175 [hep-ph].982
[60] T. Sjöstrand, S. Mrenna and P. Skands, A Brief Introduction to PYTHIA 8.1,983
Comput. Phys. Commun. 178 (2008) 852–867, arXiv: 0710.3820 [hep-ph].984
[61] J. A. et al, The automated computation of tree-level and next-to-leading order differential cross985
sections, and their matching to parton shower simulations, JHEP 07 (2014) 079,986
arXiv: 1405.0301 [hep-ph].987
[62] M. Wiesemann et al, Higgs production in association with bottom quarks, JHEP 02 (2015) 132,988
arXiv: 1409.5301 [hep-ph].989
[63] T. S. et al., An Introduction to PYTHIA 8.2, Comput.Phys.Commun. 191 (2015) 159–177,990
arXiv: 1410.3012 [hep-ph].991
[64] Z. Czyczula, T. Przedzinski and Z. Was,992
TauSpinner Program for Studies on Spin Effect in tau Production at the LHC, 72 (2012) 1988,993
arXiv: 1201.0117 [hep-ph].994
9th May 2016 – 16:38 73
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[65] R. D. Ball et al., Parton distributions with LHC data, Nucl. Phys. B867 (2013) 244–289,995
arXiv: 1207.1303 [hep-ph].996
[66] GEANT4 Collaboration, S. Agostinelli et al., GEANT4 - a simulation toolkit,997
Nucl. Instrum. Meth. A 506 (2003) 250–303.998
[67] ATLAS Collaboration, Identification and energy calibration of hadronically decaying tau999
leptons with the ATLAS experiment in pp collisions at√
s=8 TeV,1000
submitted to Eur. Phys. J. C (2014), arXiv: 1412.7086 [hep-ex].1001
[68] ATLAS Collaboration, Reconstruction, Energy Calibration, and Identification of Hadronically1002
Decaying Tau Leptons in the ATLAS Experiment for Run-2 of the LHC (2015 (to be published)).1003
[69] ATLAS Collaboration, Measurement of the muon reconstruction performance of the ATLAS1004
detector using 2011 and 2012 LHC proton-proton collision data,1005
Eur.Phys.J. C 74.11 (2014) 3130, arXiv: 1407.3935 [hep-ex].1006
[70] M. Cacciari, G. P. Salam and G. Soyez, The Anti-kt jet clustering algorithm,1007
JHEP 0804 (2008) 063, arXiv: 0802.1189 [hep-ph].1008
[71] M. Cacciari and G. P. Salam, Dispelling the N**3 myth for the kt jet-finder,1009
Phys.Lett. B641 (2006) 57–61, arXiv: hep-ph/0512210 [hep-ph].1010
[72] A. F. T. Group, ATLAS Flavour Tagging group recommendation for 2015 data (),1011
url: https://twiki.cern.ch/twiki/bin/view/AtlasProtected/BTagCalib2015.1012
[73] ATLAS Collaboration, Pile-up subtraction and suppression for jets in ATLAS,1013
ATLAS-CONF-2013-083 (2013), url: http://cds.cern.ch/record/1570994..1014
[74] ATLAS Collaboration, Performance of Missing Transverse Momentum Reconstruction in ATLAS1015
studied in Proton–Proton Collisions recorded in 2012 at 8 TeV,1016
ATLAS-CONF-2013-082 (2013), url: https://cds.cern.ch/record/1570993.1017
[75] Z. Czyczula, T. Przedzinski and Z. Was,1018
TauSpinner Program for Studies on Spin Effect in tau Production at the LHC,1019
Eur.Phys.J. C72 (2012) 1988, arXiv: 1201.0117 [hep-ph].1020
[76] A. Kaczmarska et al., Application of TauSpinner for Studies on τ-Lepton Polarization and Spin1021
Correlations in Z , W and H Decays at the LHC, Acta Phys.Polon. B45.10 (2014) 1921–1946,1022
arXiv: 1402.2068 [hep-ph].1023
[77] S. Banerjee et al.,1024
Ascertaining the spin for new resonances decaying into tau+ tau- at Hadron Colliders,1025
Eur.Phys.J. C73.2 (2013) 2313, arXiv: 1212.2873 [hep-ph].1026
[78] P. Bechtle et al., ‘Search for strongly produced supersymmetry in 13 TeV p–p collisions with1027
tau-leptons, jets and missing transverse energy in the final state.’,1028
tech. rep. ATL-COM-PHYS-2015-1126,1029
support note for planned SUSY CONF or paper on 2015 LHC data: CERN, 2015,1030
url: https://cds.cern.ch/record/2050716.1031
[79] J Butterworth et al.,1032
‘Single Boson and Diboson Production Cross Sections in pp Collisions at sqrts=7 TeV’,1033
tech. rep. ATL-COM-PHYS-2010-695, CERN, 2010,1034
url: https://cds.cern.ch/record/1287902.1035
9th May 2016 – 16:38 74
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[80] J. M. B. et al., THE TOOLS AND MONTE CARLO WORKING GROUP Summary Report from1036
the Les Houches 2009 Workshop on TeV Colliders (2010), arXiv: 1003.1643 [hep-ph].1037
[81] J. M. B. et al., PDF4LHC recommendations for LHC Run II (2015),1038
arXiv: 1510.03865 [hep-ph].1039
[82] H.-L. L. et al., New parton distributions for collider physics (2010),1040
arXiv: 1007.2241 [hep-ph].1041
[83] N. Collaboration, Parton distributions for the LHC Run II (2014), arXiv: 1410.8849 [hep-ph].1042
[84] S. D. et al., The CT14 Global Analysis of Quantum Chromodynamics (2015),1043
arXiv: 1506.07443 [hep-ph].1044
[85] A. M. et al.,1045
Heavy-quark mass dependence in global PDF analyses and 3- and 4-flavour parton distributions1046
(2010), arXiv: 1007.2624 [hep-ph].1047
[86] A. B. et al., LHAPDF6: parton density access in the LHC precision era (2014),1048
arXiv: 1412.7420 [hep-ph].1049
[87] ATLAS Run 1 Pythia8 tunes (2014), url: https://cds.cern.ch/record/1966419.1050
[88] Measurement of the transverse momentum distribution of Z/gamma* bosons in proton-proton1051
collisions at roots = 7 TeV with the ATLAS detector : Update with 4.7 fb-1 of the previous1052
measurement at this energy. (2013), url: https://cds.cern.ch/record/1513133.1053
[89] G. Artoni et al., ‘Search for resonant and non-resonant phenomena in the dilepton channel using1054
proton-proton collisions at√
s = 13 TeV with the ATLAS detector’,1055
tech. rep. ATL-COM-PHYS-2015-526, CERN, 2015,1056
url: https://cds.cern.ch/record/2025566.1057
[90] O Boeriu et al., A search for high-mass resonances decaying to τ+τ− in pp collisions at√
s = 81058
TeV with the ATLAS detector, ATL-PHYS-INT-2015-006 (2015),1059
url: https://cds.cern.ch/record/2006867.1060
[91] S. Banerjee et al.,1061
Ascertaining the spin for new resonances decaying into tau+ tau- at Hadron Colliders,1062
73 (2013) 2313, arXiv: 1212.2873 [hep-ph].1063
[92] A. Kaczmarska et al., Application of TauSpinner for studies on tau-lepton polarization and spin1064
correlations in Z, W and H decays at LHC (2014), arXiv: 1402.2068 [hep-ph].1065
[93] D. J. Muller and S. Nandi, Topflavor: a separate SU (2) for the third family,1066
Physics Letters B 383 (Feb. 1996) 345–350, eprint: hep-ph/9602390.1067
[94] K. Hsieh et al., Global analysis of general SU (2) × SU (2) ×U (1) models with precision data,1068
82, 035011 (Aug. 2010) 035011, arXiv: 1003.3482 [hep-ph].1069
[95] Q.-H. Cao et al.,1070
Discovery and identification of W ′ and Z ′ in SU (2)1 ⊗ SU (2)2 ⊗ U (1)X models at the LHC,1071
86, 095010 (Nov. 2012) 095010, arXiv: 1205.3769 [hep-ph].1072
[96] Y. G. Kim and K. Y. Lee,1073
Direct search for heavy gauge bosons at the LHC in the nonuniversal SU (2) model (May 2014),1074
arXiv: 1405.7762 [hep-ph].1075
[97] K. Y. Lee, Unitarity violation of the CKM matrix in a nonuniversal gauge interaction model,1076
71, 115008 (June 2005) 115008, eprint: hep-ph/0410381.1077
9th May 2016 – 16:38 75
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
[98] K. Y. Lee, Lepton flavor violation in a nonuniversal gauge interaction model,1078
82, 097701 (Nov. 2010) 097701, arXiv: 1009.0104 [hep-ph].1079
[99] O Boeriu et al., A search for high-mass resonances decaying to τ+τ− in pp collisions at√
s = 81080
TeV with the ATLAS detector, ATL-COM-PHYS-2014-276 (2014),1081
url: https://cds.cern.ch/record/1694306.1082
[100] A. L. Read, Presentation of search results: the CLs technique, J. Phys. G 28 (2002) 2693–2704.1083
[101] G. Cowan, K. Cranmer, E. Gross and O. Vitells,1084
Asymptotic formulae for likelihood-based tests of new physics, Eur. Phys. J. C 71 (2011) 1554,1085
arXiv: 1007.1727 [physics.data-an].1086
[102] Search for Neutral MSSM Higgs Bosons H/A to τlepτhad and Z’ to τlepτhad produced in 13 TeV1087
collisions with the ATLAS detector (2016), url: https://cds.cern.ch/record/2131232.1088
[103] A. Elagin et al., A New Mass Reconstruction Technique for Resonances Decaying to di-tau1089
(2010), * Temporary entry *, arXiv: 1012.4686 [hep-ex].1090
[104] B. Bullock, K. Hagiwara and A. D. Martin,1091
Tau polarization and its correlations as a probe of new physics,1092
Nucl.Phys. B395 (1993) 499–533.1093
[105] A. Rouge, Tau decays as polarization analysers, In *Orsay 1990, Proceedings, Tau lepton1094
physics* (QCD161:W671:1990) 213-222, and Preprint - Rouge, A. (rec.Mar.91) 10 p (1991).1095
[106] Search for Neutral MSSM Higgs Bosons H/A to τhadτhad produced in 13 TeV collisions with the1096
ATLAS detector (2015), url: https://cds.cern.ch/record/2033060.1097
9th May 2016 – 16:38 76
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Auxiliary material1098
A. Post-fit Distributions for Higgs Search Signal Regions1099
In Figures 50-53 a selection of post-fit distributions for the combined τhadτhad + τlepτhad conditional µ = 01100
fit is shown for the b-veto and b-tag categories.1101
Eve
nts
/ G
eV
4−10
3−10
2−10
1−10
1
10
210
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
[GeV]totTm
200 300 400 500 600 700 800 900 1000Da
ta/P
red
.
00.5
11.5
2
(a)
Eve
nts
/ G
eV
3−10
2−10
1−10
1
10
210
310
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
[GeV]miss
TE
0 20 40 60 80 100 120 140 160 180 200Da
ta/P
red
.
0.81
1.2
(b)
Eve
nts
/ G
eV
3−10
2−10
1−10
1
10
210
310
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
[GeV] 0τ
Tp
100 150 200 250 300 350 400Da
ta/P
red
.
00.5
11.5
2
(c)
Eve
nts
/ G
eV
3−10
2−10
1−10
1
10
210
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
[GeV] 1τ
Tp
60 80 100 120 140 160 180 200 220 240 260Da
ta/P
red
.
00.5
11.5
2
(d)
Figure 50: Postfit variable distributions in the b-veto category for the combined τhadτhad + τlepτhad fit: (a) mtotT , (b)
EmissT , (c) Leading τhad pT, (d) Subleading τhad pT.
9th May 2016 – 16:38 77
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Eve
nts
1
10
210
310
410
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
0τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata
/Pre
d.
0.8
1
1.2
(a)
Eve
nts
1
10
210
310
410
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata
/Pre
d.
0.8
1
1.2
(b)
Eve
nts
1−10
1
10
210
310
410
510 Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
jetN
0 1 2 3 4 5Da
ta/P
red
.
0.5
1
1.5
(c)
Eve
nts
3−10
2−10
1−10
1
10
210
310
410
510 Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
bjetN
0 1 2 3 4 5Da
ta/P
red
.
0.9
1
1.1
(d)
Eve
nts
/ G
eV
3−10
2−10
1−10
1
10
210
310
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
[GeV]jet 0
Tp
0 50 100 150 200 250 300Da
ta/P
red
.
0.5
1
1.5
(e)
Eve
nts
/ G
eV
3−10
2−10
1−10
1
10
210Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
bveto
[GeV]T
E∑200 300 400 500 600 700 800D
ata
/Pre
d.
00.5
11.5
2
(f)
Figure 51: Postfit variable distributions in the b-veto category for the combined τhadτhad + τlepτhad fit: (a) Leadingτhad η, (b) Subleading τhad η, (c) Njet, (d) Nb−jet, (e) Leading jet pT, (f) Scalar sum of the ET of the objects used inthe Emiss
T calculation, ΣET.
9th May 2016 – 16:38 78
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Eve
nts
/ G
eV
4−10
3−10
2−10
1−10
1
10Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
[GeV]totTm
150 200 250 300 350 400 450 500 550 600Da
ta/P
red
.
0.5
1
1.5
(a)
Eve
nts
/ G
eV
4−10
3−10
2−10
1−10
1
10 Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
[GeV]miss
TE
0 20 40 60 80 100 120 140 160 180 200Da
ta/P
red
.
00.5
11.5
2
(b)
Eve
nts
/ G
eV
5−10
4−10
3−10
2−10
1−10
1
10Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
[GeV] 0τ
Tp
100 150 200 250 300 350 400Da
ta/P
red
.
0.5
1
1.5
(c)
Eve
nts
/ G
eV
5−10
4−10
3−10
2−10
1−10
1
10Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
[GeV] 1τ
Tp
60 80 100 120 140 160 180 200 220 240 260Da
ta/P
red
.
0.5
1
1.5
(d)
Figure 52: Postfit variable distributions in the b-tag category for the combined τhadτhad + τlepτhad fit: (a) mtotT , (b)
EmissT , (c) Leading τhad pT, (d) Subleading τhad pT.
9th May 2016 – 16:38 79
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Eve
nts
2−10
1−10
1
10
210
310
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
0τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata
/Pre
d.
0
0.5
1
1.5
2
(a)
Eve
nts
2−10
1−10
1
10
210
310 Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
1τη2.5− 2− 1.5− 1− 0.5− 0 0.5 1 1.5 2 2.5D
ata
/Pre
d.
0.5
1
1.5
(b)
Eve
nts
3−10
2−10
1−10
1
10
210
310
410 Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
jetN
0 1 2 3 4 5Da
ta/P
red
.
0.5
1
1.5
(c)
Eve
nts
3−10
2−10
1−10
1
10
210
310
Data ττ→H/A
= 20β= 500 GeV, tan AmMultijet
+ jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
bjetN
0 1 2 3 4 5Da
ta/P
red
.
0.5
1
1.5
(d)
Eve
nts
/ G
eV
4−10
3−10
2−10
1−10
1
10Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
[GeV]jet 0
Tp
0 50 100 150 200 250 300Da
ta/P
red
.
0.5
1
1.5
(e)
Eve
nts
/ G
eV
4−10
3−10
2−10
1−10
1Data
ττ→H/A = 20β= 500 GeV, tan Am
Multijet + jetsττ→Z + jetsντ→W
ttbar, single topOthersUncertaintyPrefit background
ATLAS Internal
1
Ldt = 3.2 fb∫ = 13 TeV s
hadτ
hadτ→H/A
btag
[GeV]T
E∑200 300 400 500 600 700 800D
ata
/Pre
d.
00.5
11.5
2
(f)
Figure 53: Postfit variable distributions in the b-tag category for the combined τhadτhad + τlepτhad fit: (a) Leadingτhad η, (b) Subleading τhad η, (c) Njet, (d) Nb−jet, (e) Leading jet pT, (f) Scalar sum of the ET of the objects used inthe Emiss
T calculation, ΣET.
9th May 2016 – 16:38 80
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
B. Statistical Analysis Fit Results For Separate Categories1102
This section lists plots for the separate b-tag and b-veto fits with the impact of systematic uncertainties1103
on the fitted signal strength and variations of the nuisance parameters from their nominal values in units1104
of their uncertainty values. For each mass point a value of tan β close to the limit was chosen for the1105
selection of plots shown here.1106
2− 1.5− 1− 0.5− 0 0.5 1 1.5 2
alpha_ATLAS_btagEffSfEigen_C_1
alpha_ATLAS_JERNP1
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_AU_ggH_MA300
alpha_ATLAS_JETNP3
alpha_ATLAS_TES_AF2
alpha_ATLAS_JETNP1
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_btagEffSfEigen_C_0
alpha_ATLAS_btagEffSfEigen_Light_0
alpha_ATLAS_xsec_Z
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_TES_MODEL
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_PRW
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_TAURECO
alpha_ATLAS_JVT
alpha_ATLAS_LUMI
alpha_ATLAS_TES_INSITU
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_xsec_Top
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_TAUID
alpha_ATLAS_AU_bbH_MA300
alpha_ATLAS_TAUTRIG
alpha_ATLAS_HADHAD_FF
alpha_ATLAS_TTBAR_NORM
µ∆
0.2− 0.15− 0.1− 0.05− 0 0.05 0.1 0.15 0.2
θ∆)/0θ - θ(1.5− 1− 0.5− 0 0.5 1 1.5
1 standard deviation
µPrefit Impact on
µPostfit Impact on
b-tag category
=15β=300 GeV, tanAm
(a)
2− 1.5− 1− 0.5− 0 0.5 1 1.5 2
alpha_ATLAS_AU_ggH_MA500
alpha_ATLAS_btagEffSfEigen_Light_1
alpha_ATLAS_JETNP3
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_JETNP1
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_JERNP1
alpha_ATLAS_btagEffSfEigen_C_1
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_btagEffSfEigen_C_0
alpha_ATLAS_btagEffSfEigen_Light_0
alpha_ATLAS_xsec_Z
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_TES_MODEL
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_PRW
alpha_ATLAS_TAURECO
alpha_ATLAS_JVT
alpha_ATLAS_LUMI
alpha_ATLAS_HADHAD_FF
alpha_ATLAS_xsec_Top
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_TES_INSITU
alpha_ATLAS_TAUID
alpha_ATLAS_TAUTRIG
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_AU_bbH_MA500
alpha_ATLAS_TTBAR_NORM
µ∆
0.15− 0.1− 0.05− 0 0.05 0.1 0.15
θ∆)/0θ - θ(1− 0.5− 0 0.5 1
1 standard deviation
µPrefit Impact on
µPostfit Impact on
b-tag category
=25β=500 GeV, tanAm
(b)
3− 2− 1− 0 1 2 3
alpha_ATLAS_JETNP3
alpha_ATLAS_JETNP2
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_btagEffSfEigen_Light_2
alpha_ATLAS_AU_ggH_MA1000
alpha_ATLAS_JERNP1
alpha_ATLAS_btagEffSfEigen_C_1
alpha_ATLAS_TES_MODEL
alpha_ATLAS_btagEffSfEigen_C_0
alpha_ATLAS_btagEffSfEigen_Light_0
alpha_ATLAS_xsec_Z
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_HADHAD_FF
alpha_ATLAS_JETNP1
alpha_ATLAS_TAURECO_HIGHPT
alpha_ATLAS_TES_INSITU
alpha_ATLAS_PRW
alpha_ATLAS_xsec_Top
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_JVT
alpha_ATLAS_TAURECO
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_TTBAR_NORM
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_LUMI
alpha_ATLAS_TAUID
alpha_ATLAS_AU_bbH_MA1000
alpha_ATLAS_TAUTRIG
µ∆
0.2− 0.1− 0 0.1 0.2
θ∆)/0θ - θ(2− 1− 0 1 2
1 standard deviation
µPrefit Impact on
µPostfit Impact on
b-tag category
=60β=1000 GeV, tanAm
(c)
Figure 54: b-tag category: Impact of the systematic uncertainties on the fitted signal strength and variations of thenuisance parameters from their nominal values in units of their uncertainty values for mA/H = 300 GeV, 500 GeVand 1000 GeV. The values of tan β correspond to the mmod+
hscenario and are chosen to be close to the expected
limit.
9th May 2016 – 16:38 81
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
2− 1.5− 1− 0.5− 0 0.5 1 1.5 2
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_xsec_Top
alpha_ATLAS_btagEffSfEigen_B_1
alpha_ATLAS_TTBAR_NORM
alpha_ATLAS_JETNP1
alpha_ATLAS_JERNP1
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_PRW
alpha_ATLAS_TES_AF2
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_AU_ggH_MA300
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_JVT
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_TES_MODEL
alpha_ATLAS_xsec_Z
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_TES_INSITU
alpha_ATLAS_TAURECO
alpha_ATLAS_LUMI
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_AU_bbH_MA300
alpha_ATLAS_HADHAD_FF
alpha_ATLAS_TAUID
alpha_ATLAS_TAUTRIG
µ∆
0.4− 0.3− 0.2− 0.1− 0 0.1 0.2 0.3 0.4
θ∆)/0θ - θ(1.5− 1− 0.5− 0 0.5 1 1.5
1 standard deviation
µPrefit Impact on
µPostfit Impact on
b-veto category
=15β=300 GeV, tanAm
(a)
2− 1.5− 1− 0.5− 0 0.5 1 1.5 2
alpha_ATLAS_TTBAR_NORM
alpha_ATLAS_JETNP1
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_xsec_Top
alpha_ATLAS_JERNP1
alpha_ATLAS_btagEffSfEigen_B_1
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_AU_ggH_MA500
alpha_ATLAS_TES_MODEL
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_PRW
alpha_ATLAS_JVT
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_AU_bbH_MA500
alpha_ATLAS_TAURECO
alpha_ATLAS_LUMI
alpha_ATLAS_xsec_Z
alpha_ATLAS_TES_INSITU
alpha_ATLAS_HADHAD_FF
alpha_ATLAS_TAUID
alpha_ATLAS_TAUTRIG
alpha_ATLAS_TES_DETECTOR
µ∆
0.2− 0.1− 0 0.1 0.2
θ∆)/0θ - θ(1.5− 1− 0.5− 0 0.5 1 1.5
1 standard deviation
µPrefit Impact on
µPostfit Impact on
b-veto category
=25β=500 GeV, tanAm
(b)
3− 2− 1− 0 1 2 3
alpha_ATLAS_btagEffSfEigen_B_1
alpha_ATLAS_JERNP1
alpha_ATLAS_xsec_Top
alpha_ATLAS_TTBAR_NORM
alpha_ATLAS_AU_ggH_MA1000
alpha_ATLAS_JETNP1
alpha_ATLAS_PRW
alpha_ATLAS_JVT
alpha_ATLAS_xsec_Diboson
alpha_ATLAS_TAURECO_HIGHPT
alpha_ATLAS_TES_MODEL
alpha_ATLAS_btagEffSfEigen_B_0
alpha_ATLAS_TAURECO
alpha_ATLAS_TAUELEOLR
alpha_ATLAS_TAUTRIG
alpha_ATLAS_LUMI
alpha_ATLAS_HADHAD_WTAUNUREWEIGHT
alpha_ATLAS_HADHAD_FR
alpha_ATLAS_TAUID
alpha_ATLAS_TAUID_HIGHPT
alpha_ATLAS_xsec_Z
alpha_ATLAS_TES_DETECTOR
alpha_ATLAS_HADHAD_FF
alpha_ATLAS_TES_INSITU
alpha_ATLAS_AU_bbH_MA1000
µ∆
0.2− 0.15− 0.1− 0.05− 0 0.05 0.1 0.15 0.2
θ∆)/0θ - θ(2− 1− 0 1 2
1 standard deviation
µPrefit Impact on
µPostfit Impact on
b-veto category
=60β=1000 GeV, tanAm
(c)
Figure 55: b-veto category: Impact of the systematic uncertainties on the fitted signal strength and variations of thenuisance parameters from their nominal values in units of their uncertainty values for mA/H = 300 GeV, 500 GeVand 1000 GeV. The values of tan β correspond to the mmod+
hscenario and are chosen to be close to the expected
limit.
9th May 2016 – 16:38 82
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
C. Asymptotic Approximation Checks1107
For the highest mtotT bin in the b-tag category of the Higgs analysis and the high mass hypotheses in1108
the Z’ analysis, the number of expected events is rather small (∼ 1). To make sure that the asymptotic1109
approximation is still valid for these cases, and therefore the asymptotic calculation can be used to1110
determine the limits, toys have been generated with µ = 0 and are compared to the χ2-distribution with1111
one degree of freedom. This is shown for selected high mass points in Figures 56-58.1112
test statistic
0 2 4 6 8 10 12 14 16 18 20
a.u.
4−10
3−10
2−10
1−10 = 0µ
= 1dof distribution for n2χ
Figure 56: Distribution of the test statistic qµ of µ = 0 toys generated for the b-tag+b-veto workspace for the hadhadHiggs search at mA = 1000 GeV, tan β = 50. A χ2 distribution with one degree of freedom is drawn and showsgood agreement with the toys.
9th May 2016 – 16:38 83
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
test statistic
0 2 4 6 8 10 12 14 16 18
a.u.
4−10
3−10
2−10
1−10 = 0µ
= 1dof distribution for n2χ
Figure 57: Distribution of the test statistic qµ of µ = 0 toys generated for the τlepτhad+τhadτhad workspace for the Z’SSM search at mZ′ = 2500 GeV. A χ2 distribution with one degree of freedom is drawn and shows good agreementwith the toys.
9th May 2016 – 16:38 84
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
test statistic
0 2 4 6 8 10 12 14 16 18
a.u.
4−10
3−10
2−10
1−10 = 0µ
= 1dof distribution for n2χ
Figure 58: Distribution of the test statistic qµ of µ = 0 toys generated for the τlepτhad+τhadτhad workspace for the Z’SSM search at mZ′ = 2500 GeV.. A χ2 distribution with one degree of freedom is drawn and shows good agreementwith the toys.
9th May 2016 – 16:38 85
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
D. MC Samples1113
This section contains the names and the cross sections of the MC samples used. Unless otherwise stated1114
samples are used from theHIGG4D4derivationwith sample tage4213_s2608_s2183_r7326_r6282_p2463.1115
9th May 2016 – 16:38 86
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Table 19: MC15 samples used in this version of the note.DID Sample name cross section [pb]
341877 aMCNloPy8_bbH300_yb2_tautauhh341878 aMCNloPy8_bbH350_yb2_tautauhh341879 aMCNloPy8_bbH400_yb2_tautauhh341880 aMCNloPy8_bbH500_yb2_tautauhh341881 aMCNloPy8_bbH600_yb2_tautauhh341882 aMCNloPy8_bbH700_yb2_tautauhh341883 aMCNloPy8_bbH800_yb2_tautauhh341885 aMCNloPy8_bbH1000_yb2_tautauhh341917 aMCNloPy8_bbH1200_yb2_tautauhh342311 PoPy8_ggH300W2_tautauhh342313 PoPy8_ggH350W3_tautauhh342315 PoPy8_ggH400W5_tautauhh342317 PoPy8_ggH500W5_tautauhh342319 PoPy8_ggH600W10_tautauhh342321 PoPy8_ggH700W20_tautauhh342323 PoPy8_ggH800W20_tautauhh342327 PoPy8_ggH1000W30_tautauhh342331 PoPy8_ggH1200W40_tautauhh410000 PowhegPythiaEvtGen_P2012_ttbar_hdamp172p5_nonallhad 696.12410001 PowhegPythiaEvtGen_P2012radHi_ttbar_hdamp345_down_nonallhad.merge 696.12410002 PowhegPythiaEvtGen_P2012radLo_ttbar_hdamp172_up_nonallhad 696.12410003 aMcAtNloHerwigppEvtGen_ttbar_nonallhad 696.12410004 PowhegHerwigppEvtGen_UEEE5_ttbar_hdamp172p5_nonallhad 696.12410006 PowhegPythia8EvtGen_A14_ttbar_hdamp172p5_nonallhad 696.12410007 .PowhegPythiaEvtGen_P2012_ttbar_hdamp172p5_allhad 696.21410011 PowhegPythiaEvtGen_P2012_singletop_tchan_lept_top 43.739410012 PowhegPythiaEvtGen_P2012_singletop_tchan_lept_antitop 25.778410013 PowhegPythiaEvtGen_P2012_Wt_inclusive_top 34.009410014 PowhegPythiaEvtGen_P2012_Wt_inclusive_antitop 33.989410015 PowhegPythiaEvtGen_P2012_Wt_dilepton_top 3.5835410016 PowhegPythiaEvtGen_P2012_Wt_dilepton_antitop 3.5814407018 PowhegPythiaEvtGen_P2012CT10_Wt_inclusive_top_HT500 3.00848407019 PowhegPythiaEvtGen_P2012CT10_Wt_inclusive_top_MET200 0.383707407020 PowhegPythiaEvtGen_P2012CT10_Wt_inclusive_tbar_HT500 3.00514407021 PowhegPythiaEvtGen_P2012CT10_Wt_inclusive_tbar_MET200 0.382686410025 PowhegPythiaEvtGen_P2012_SingleTopSchan_noAllHad_top 2.0517410026 PowhegPythiaEvtGen_P2012_SingleTopSchan_noAllHad_antitop 1.2615361106 PowhegPythia8EvtGen_AZNLOCTEQ6L1_Zee 97.5316361107 PowhegPythia8EvtGen_AZNLOCTEQ6L1_Zmumu 97.5316361108 PowhegPythia8EvtGen_AZNLOCTEQ6L1_Ztautau 97.5316361063 Sherpa_CT10_llll 12.583361064 Sherpa_CT10_lllvSFMinus 1.8446361065 Sherpa_CT10_lllvOFMinus 3.6235361066 Sherpa_CT10_lllvSFPlus 2.5656361067 Sherpa_CT10_lllvOFPlus 5.0169
9th May 2016 – 16:38 87
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Table 20: MC15 samples used in this version of the note.DID Sample name cross section [pb]
301015 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_3500M4000 2.9e-06301005 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_800M1000 0.010607301017 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_4500M5000 3e-07301003 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_400M600 0.1955301013 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_2750M3000 1.25e-05301002 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_250M400 1.082301011 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_2250M2500 4.94e-05301008 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_1500M1750 0.0005452301004 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_600M800 0.037401301007 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_1250M1500 0.0014219301001 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_180M250 2.9212301000 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_120M180 17.478301010 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_2000M2250 0.0001039301006 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_1000M1250 0.0042582301012 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_2500M2750 2.45e-05301009 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_1750M2000 0.0002299301018 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_5000M 1e-07301016 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_4000M4500 9e-07301014 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYee_3000M3500 1e-05301027 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_1250M1500 0.0014219301026 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_1000M1250 0.0042582301031 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_2250M2500 4.94e-05301021 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_180M250 2.9212301020 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_120M180 17.478301038 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_5000M 1e-07301022 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_250M400 1.082301023 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_400M600 0.1955301030 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_2000M2250 0.0001039301033 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_2750M3000 1.25e-05301024 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_600M800 0.037399301028 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_1500M1750 0.0005452301035 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_3500M4000 2.9e-06301025 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_800M1000 0.010607301037 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_4500M5000 3e-07301034 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_3000M3500 1e-05301032 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_2500M2750 2.45e-05301029 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_1750M2000 0.0002299301036 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYmumu_4000M4500 9e-07301045 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_800M1000 0.010607301053 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_2750M3000 1.25e-05301058 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_5000M 1e-07301044 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_600M800 0.037401301041 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_180M250 2.9209301057 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_4500M5000 3e-07301054 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_3000M3500 1e-05301048 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_1500M1750 0.0005452301050 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_2000M2250 0.0001039301042 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_250M400 1.082301049 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_1750M2000 0.0002299301047 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_1250M1500 0.001422301055 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_3500M4000 2.9e-06301040 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_120M180 17.48301043 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_400M600 0.1955301051 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_2250M2500 4.94e-05301056 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_4000M4500 9e-07301052 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_2500M2750 2.45e-05301046 PowhegPythia8EvtGen_AZNLOCTEQ6L1_DYtautau_1000M1250 0.0042584
9th May 2016 – 16:38 88
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Table 21: MC15 samples used in this version of the note.DID Sample name cross section [pb]
361300 Sherpa_CT10_Wenu_Pt0_70_CVetoBVeto 2.138e+04361301 Sherpa_CT10_Wenu_Pt0_70_CFilterBVeto 2.138e+04361302 Sherpa_CT10_Wenu_Pt0_70_BFilter 2.138e+04361303 Sherpa_CT10_Wenu_Pt70_140_CVetoBVeto 632.8361304 Sherpa_CT10_Wenu_Pt70_140_CFilterBVeto 632.8361305 Sherpa_CT10_Wenu_Pt70_140_BFilter 632.8361306 Sherpa_CT10_Wenu_Pt140_280_CVetoBVeto 90.12361307 Sherpa_CT10_Wenu_Pt140_280_CFilterBVeto 90.12361308 Sherpa_CT10_Wenu_Pt140_280_BFilter 90.12361309 Sherpa_CT10_Wenu_Pt280_500_CVetoBVeto 5.747361310 Sherpa_CT10_Wenu_Pt280_500_CFilterBVeto 5.747361311 Sherpa_CT10_Wenu_Pt280_500_BFilter 5.747361312 Sherpa_CT10_Wenu_Pt500_700_CVetoBVeto 0.3479361313 Sherpa_CT10_Wenu_Pt500_700_CFilterBVeto 0.3479361314 Sherpa_CT10_Wenu_Pt500_700_BFilter 0.3479361315 Sherpa_CT10_Wenu_Pt700_1000_CVetoBVeto 0.06107361316 Sherpa_CT10_Wenu_Pt700_1000_CFilterBVeto 0.06107361317 Sherpa_CT10_Wenu_Pt700_1000_BFilter 0.06107361318 Sherpa_CT10_Wenu_Pt1000_2000_CVetoBVeto 0.006643361319 Sherpa_CT10_Wenu_Pt1000_2000_CFilterBVeto 0.006643361320 Sherpa_CT10_Wenu_Pt1000_2000_BFilter 0.006643361321 Sherpa_CT10_Wenu_Pt2000_E_CMS_CVetoBVeto 2.659e-05361322 Sherpa_CT10_Wenu_Pt2000_E_CMS_CFilterBVeto 2.659e-05361323 Sherpa_CT10_Wenu_Pt2000_E_CMS_BFilter 2.659e-05361324 Sherpa_CT10_Wmunu_Pt0_70_CVetoBVeto 2.138e+04361325 Sherpa_CT10_Wmunu_Pt0_70_CFilterBVeto 2.138e+04361326 Sherpa_CT10_Wmunu_Pt0_70_BFilter 2.138e+04361327 Sherpa_CT10_Wmunu_Pt70_140_CVetoBVeto 632.8361328 Sherpa_CT10_Wmunu_Pt70_140_CFilterBVeto 632.8361329 Sherpa_CT10_Wmunu_Pt70_140_BFilter 632.8361330 Sherpa_CT10_Wmunu_Pt140_280_CVetoBVeto 90.12361331 Sherpa_CT10_Wmunu_Pt140_280_CFilterBVeto 90.12361332 Sherpa_CT10_Wmunu_Pt140_280_BFilter 90.12361333 Sherpa_CT10_Wmunu_Pt280_500_CVetoBVeto 5.747361334 Sherpa_CT10_Wmunu_Pt280_500_CFilterBVeto 5.747361335 Sherpa_CT10_Wmunu_Pt280_500_BFilter 5.747361336 Sherpa_CT10_Wmunu_Pt500_700_CVetoBVeto 0.3479361337 Sherpa_CT10_Wmunu_Pt500_700_CFilterBVeto 0.3479361338 Sherpa_CT10_Wmunu_Pt500_700_BFilter 0.3479361339 Sherpa_CT10_Wmunu_Pt700_1000_CVetoBVeto 0.06107361340 Sherpa_CT10_Wmunu_Pt700_1000_CFilterBVeto 0.06107361341 Sherpa_CT10_Wmunu_Pt700_1000_BFilter 0.06107361342 Sherpa_CT10_Wmunu_Pt1000_2000_CVetoBVeto 0.006643361343 Sherpa_CT10_Wmunu_Pt1000_2000_CFilterBVeto 0.006643361344 Sherpa_CT10_Wmunu_Pt1000_2000_BFilter 0.006643361345 Sherpa_CT10_Wmunu_Pt2000_E_CMS_CVetoBVeto 2.659e-05361346 Sherpa_CT10_Wmunu_Pt2000_E_CMS_CFilterBVeto 2.659e-05361347 Sherpa_CT10_Wmunu_Pt2000_E_CMS_BFilter 2.659e-05
9th May 2016 – 16:38 89
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Table 22: MC15 samples used in this version of the note.DID Sample name cross section [pb]
361348 Sherpa_CT10_Wtaunu_Pt0_70_CVetoBVeto 2.138e+04361349 Sherpa_CT10_Wtaunu_Pt0_70_CFilterBVeto 2.138e+04361350 Sherpa_CT10_Wtaunu_Pt0_70_BFilter 2.138e+04361351 Sherpa_CT10_Wtaunu_Pt70_140_CVetoBVeto 632.8361352 Sherpa_CT10_Wtaunu_Pt70_140_CFilterBVeto 632.8361353 Sherpa_CT10_Wtaunu_Pt70_140_BFilter 632.8361354 Sherpa_CT10_Wtaunu_Pt140_280_CVetoBVeto 90.12361355 Sherpa_CT10_Wtaunu_Pt140_280_CFilterBVeto 90.12361356 Sherpa_CT10_Wtaunu_Pt140_280_BFilter 90.12361357 Sherpa_CT10_Wtaunu_Pt280_500_CVetoBVeto 5.747361358 Sherpa_CT10_Wtaunu_Pt280_500_CFilterBVeto 5.747361359 Sherpa_CT10_Wtaunu_Pt280_500_BFilter 5.747361360 Sherpa_CT10_Wtaunu_Pt500_700_CVetoBVeto 0.3479361361 Sherpa_CT10_Wtaunu_Pt500_700_CFilterBVeto 0.3479361362 Sherpa_CT10_Wtaunu_Pt500_700_BFilter 0.3479361363 Sherpa_CT10_Wtaunu_Pt700_1000_CVetoBVeto 0.06107361364 Sherpa_CT10_Wtaunu_Pt700_1000_CFilterBVeto 0.06107361365 Sherpa_CT10_Wtaunu_Pt700_1000_BFilter 0.06107361366 Sherpa_CT10_Wtaunu_Pt1000_2000_CVetoBVeto 0.006643361367 Sherpa_CT10_Wtaunu_Pt1000_2000_CFilterBVeto 0.006643361368 Sherpa_CT10_Wtaunu_Pt1000_2000_BFilter 0.006643361369 Sherpa_CT10_Wtaunu_Pt2000_E_CMS_CVetoBVeto 2.659e-05361370 Sherpa_CT10_Wtaunu_Pt2000_E_CMS_CFilterBVeto 2.659e-05361371 Sherpa_CT10_Wtaunu_Pt2000_E_CMS_BFilter 2.659e-05
Table 23: MC15 samples used in this version of the note.DID Sample name cross section [pb]
303437 Pythia8EvtGen_A14NNPDF23LO_DYtautau_120M180 1.3842e+01303438 Pythia8EvtGen_A14NNPDF23LO_DYtautau_180M250 2.3352e+00303439 Pythia8EvtGen_A14NNPDF23LO_DYtautau_250M400 8.6526e-01303440 Pythia8EvtGen_A14NNPDF23LO_DYtautau_400M600 1.5594e-01303441 Pythia8EvtGen_A14NNPDF23LO_DYtautau_600M800 2.9643e-02303442 Pythia8EvtGen_A14NNPDF23LO_DYtautau_800M1000 8.3148e-03303443 Pythia8EvtGen_A14NNPDF23LO_DYtautau_1000M1250 3.3072e-03303444 Pythia8EvtGen_A14NNPDF23LO_DYtautau_1250M1500 1.0955e-03303445 Pythia8EvtGen_A14NNPDF23LO_DYtautau_1500M1750 4.1817e-04303446 Pythia8EvtGen_A14NNPDF23LO_DYtautau_1750M2000 1.7610e-04303447 Pythia8EvtGen_A14NNPDF23LO_DYtautau_2000M2250 7.9838e-05303448 Pythia8EvtGen_A14NNPDF23LO_DYtautau_2250M2500 3.8223e-05303449 Pythia8EvtGen_A14NNPDF23LO_DYtautau_2500M2750 1.9088e-05303450 Pythia8EvtGen_A14NNPDF23LO_DYtautau_2750M3000 9.8673e-06303451 Pythia8EvtGen_A14NNPDF23LO_DYtautau_3000M3500 8.0521e-06303452 Pythia8EvtGen_A14NNPDF23LO_DYtautau_3500M4000 2.4178e-06303453 Pythia8EvtGen_A14NNPDF23LO_DYtautau_4000M4500 7.5696e-07303454 Pythia8EvtGen_A14NNPDF23LO_DYtautau_4500M5000 2.4277e-07303455 Pythia8EvtGen_A14NNPDF23LO_DYtautau_5000M 1.1662e-07
9th May 2016 – 16:38 90
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
E. Signal Samples1116
E.1. Signal acceptance systematics1117
E.2. Validation of the bbH fast simulation1118
Signal samples for the bbH production processwere generated usingAltfast-II (AF2) [email protected]
Validation tests were performed to ensure that AF2 and Full Simulation (FS)n results were comparable.1120
Test samples of 280500(277348) events were generated using AF2(FS) at the 1 TeV mass point, with a1121
scale factor applied to FS samples to account for the difference in sample size.1122
In the lep-had channel, the leading Tau pT (Figures 59 and 64), EmissT (Figures 60 and 65), Visible1123
Mass (Figures 61 and 66), MOSAIC (mH ) mass reconstruction (Figures 62 and 67) and MMC mass1124
reconstruction (Figures 63 and 68) variables were compared directly. For both samples, no scale factors1125
(other than that accounting for the event number discrepancy) or weights are included; raw numbers only1126
are used. Variables are compared both before the lep-had cutflow (with all high-level trigger cuts applied)1127
(Figures 59,60,61,62 and 63) and after the full lep-had cutflow (Figures 64,65,66,67 and 68).1128
Figure 59: Tau pT (HLT Cuts Only), separately for e-channel (left) and µ-channel (right).
Figure 60: EmissT (HLT Cuts Only), separately for e-channel (left) and µ-channel (right).
Variations between the fast and full simulation methods are minimal, with the exception of consistently1129
lower yields in EmissT in the fast simulation. In the e-had channel, the yield of the full (fast) simulation1130
is 40002.50 ± 201.14 (40089 ± 200.22) events, giving a discrepancy of 0.216%. In the mu-had channel,1131
9th May 2016 – 16:38 91
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Figure 61: Visible Mass (HLT Cuts Only), separately for e-channel (left) and µ-channel (right).
Figure 62: MOSAIC (mH ) (HLT Cuts Only), separately for e-channel (left) and µ-channel (right).
Figure 63: MMC (HLT Cuts Only), separately for e-channel (left) and µ-channel (right).
the full (fast) yield is 45652 ± 214.87 (46331 pm 215.24), giving a discrepancy of 1.49%. These results1132
suggest that the fast simulation method is consistent with the full simulation method within approximately1133
2%.1134
9th May 2016 – 16:38 92
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Figure 64: Tau pT (All Cuts Applied), separately for e-channel (left) and µ-channel (right).
Figure 65: EmissT (All Cuts Applied), separately for e-channel (left) and µ-channel (right).
Figure 66: Visible Mass (All Cuts Applied), separately for e-channel (left) and µ-channel (right).
E.3. Z/γ∗ → Z′ reweighting validation1135
The reweighting provided by the TauSpinner algorithm, including the extension to allow reweighting for1136
BSM processes, has been extensively validated [64, 90–92]. In this section the validation of the Born-level1137
cross sections for Z ′ production that has been provided to TauSpinner is described.1138
As an additional cross-check to validate the reweighting at 13 TeV a simulated Z ′ signal sample with a1139
resonance mass of 3 TeVis compared to Z/γ∗ → ττ reweighted to a signal with the same mass. Figure 691140
9th May 2016 – 16:38 93
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Figure 67: MOSAIC (mH ) (All Cuts Applied), separately for e-channel (left) and µ-channel (right).
Figure 68: MMC (All Cuts Applied), separately for e-channel (left) and µ-channel (right).
depicts the generator level resonance mass. Reasonable agreement is found over the whole mass range.1141
Major deviations are seen at low mass due to missing inclusive Z/γ∗ → ττ sample below 120 GeV and1142
at high mass are due to statistical limitations from the Z ′ → ττ sample. The former is unproblematic as1143
none of the events will enter the final mass window.1144
Figures 70 and 71 shows various kinematic distributions of the tau leptons at generator level and the mass1145
variables of the missing transverse mass and the total transverse mass mtotT . Again1146
F. Mass Reconstruction1147
F.1. Introduction1148
In this analysis the reconstruction of the invariant mass is done mainly through three complex algorithms:1149
MMC,MOSAIC and mtotT . Studies are being done to figure out which one is the most suitable for the anal-1150
ysis. These studies focuses in several aspects of their performance, among which are the discrimination1151
power (studied as the significance of the ratio signal over background), the exactness of the reconstruction,1152
the computation-time consumption and the complexity.1153
1154
9th May 2016 – 16:38 94
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
resonance mass [TeV]
0 1 2 3 4 5 6
a.u
.
6−10
5−10
4−10
3−10
2−10
1−10
1
10
210
310
410 (3000GeV)ττZ’> (120180GeV)ττ*>γZ/ (180250GeV)ττ*>γZ/ (250400GeV)ττ*>γZ/
(400600GeV)ττ*>γZ/ (600800GeV)ττ*>γZ/ (8001000GeV)ττ*>γZ/ (10001250GeV)ττ*>γZ/
(12501500GeV)ττ*>γZ/ (15001750GeV)ττ*>γZ/ (17502000GeV)ττ*>γZ/ (20002250GeV)ττ*>γZ/
(22502500GeV)ττ*>γZ/ (25002750GeV)ττ*>γZ/ (27503000GeV)ττ*>γZ/ (30003500GeV)ττ*>γZ/
(35004000GeV)ττ*>γZ/ (40004500GeV)ττ*>γZ/ (45005000GeV)ττ*>γZ/ (5000GeV)ττ*>γZ/
(3000GeV)ττZ’> (120180GeV)ττ*>γZ/ (180250GeV)ττ*>γZ/ (250400GeV)ττ*>γZ/
(400600GeV)ττ*>γZ/ (600800GeV)ττ*>γZ/ (8001000GeV)ττ*>γZ/ (10001250GeV)ττ*>γZ/
(12501500GeV)ττ*>γZ/ (15001750GeV)ττ*>γZ/ (17502000GeV)ττ*>γZ/ (20002250GeV)ττ*>γZ/
(22502500GeV)ττ*>γZ/ (25002750GeV)ττ*>γZ/ (27503000GeV)ττ*>γZ/ (30003500GeV)ττ*>γZ/
(35004000GeV)ττ*>γZ/ (40004500GeV)ττ*>γZ/ (45005000GeV)ττ*>γZ/ (5000GeV)ττ*>γZ/
410
310
210
110
1
a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0
1
2
3
4
truth resonance mass [TeV]0 1 2 3 4 5 6
(
3000G
eV
)τ
τZ
’>
Ratio to
Figure 69: Generator-level resonance mass for Z ′ with mZ′ = 3 TeV events generated with Pythia8, and also forZ/γ∗ → ττ events generated with Pythia8 reweighted to the same mass. The left plot shows Z/γ∗ → ττ samplessplitted in the various slices while the right plot shows the inclusive Z/γ∗ → ττ.
A brief description of each algorithm is given, along with the preliminary results of the comparison1155
studies. These studies are still ongoing and the conclusions subject to later changes.1156
F.2. MMC1157
MMC stands for Missing Mass Calculator. It is an algorithm [103] developed for the Run I analysis1158
of τ decays involving neutrinos. This algorithm assumes that the missing transverse momentum is due1159
entirely to the neutrinos and performs a scan over the angles between the neutrinos and the visible τ1160
decay products. Each solution is weighted according to probability density functions that are derived from1161
simulated τ decays. Three outputs can be obtained from that analysis:1162
MaximumWeight Mass obtained from the point of phase space which has the maximum weight1163
Most Likely Mass Value of mass with the higher probability after the integration - this was the default1164
result used for Run I1165
Most Likely Neutrino 3P Mass obtained from the point with the most likely neutrinos, both optimised1166
separately.1167
MMC algorithm has to be optimised by tuning the MET resolution, especially for high mass points.1168
Studies for tuning the MMC and comparing the performance of the three different outputs are being done1169
at the moment, both for LepHad and HadHad channels.1170
F.3. mTot1171
In the Run I, the mass reconstruction was done also using the total transverse mass, (mtotT ), defined as1172
follows:1173
1174
9th May 2016 – 16:38 95
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
410
310
210
110
1
a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0
0.5
1
1.5
[GeV]T
pτtruth 500 1000 1500 2000 2500 3000 3500 4000
(
3000G
eV
)τ
τZ
’>
Ratio to
410
310
210
110
a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0
0.5
1
1.5
2
[GeV]T
vis pτtruth 500 1000 1500 2000 2500 3000 3500 4000
(
3000G
eV
)τ
τZ
’>
Ratio to
0.05
0.1
0.15
0.2
0.25
0.3
0.35a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0.5
1
1.5
η τtruth 5− 4− 3− 2− 1− 0 1 2 3 4 5
(
3000G
eV
)τ
τZ
’>
Ratio to
0.05
0.1
0.15
0.2
0.25
0.3
0.35a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0.5
1
visη τtruth 5− 4− 3− 2− 1− 0 1 2 3 4 5
(
3000G
eV
)τ
τZ
’>
Ratio to
0.020.040.060.08
0.10.120.140.160.180.2
0.220.24
a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0.95
1
1.05
φ τtruth 4− 3− 2− 1− 0 1 2 3 4
(
3000G
eV
)ττ
Z’>
Ratio to
0.020.040.060.08
0.10.120.140.160.180.2
0.220.24
a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0.95
1
1.05
visφ τtruth
4− 3− 2− 1− 0 1 2 3 4
(
3000G
eV
)ττ
Z’>
Ratio to
Figure 70: Generator-level full and visible kinematic variables of tau leptons from for Z ′ with mZ′ = 3 TeV eventsgenerated with Pythia8, and also for Z/γ∗ → ττ events generated with Pythia8 reweighted to the same mass.9th May 2016 – 16:38 96
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
410
310
210
110
a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0
1
2
3
[GeV]miss
Ttruth m
500 1000 1500 2000 2500 3000 3500 4000
(
3000G
eV
)τ
τZ
’>
Ratio to
410
310
210
a.u
.
(3000GeV)ττZ’>
ττ*>γZ/
(3000GeV)ττZ’>
ττ*>γZ/
0
1
2
[GeV]tot
Ttruth m
500 1000 1500 2000 2500 3000 3500 4000
(
3000G
eV
)τ
τZ
’>
Ratio to
Figure 71: Generator-level event mass distributions EmissT and mtot
T for Z ′ with mZ′ = 3 TeV events generated withPythia8, and also for Z/γ∗ → ττ events generated with Pythia8 reweighted to the same mass.
mtotT =
√m2T (τ1, τ2) + m2
T
(τ1, EMiss
T
)+ m2
T
(τ2, EMiss
T
)where the mT between two objects is defined as:1175
mT =√
2pT1pT2 (1 − cos∆φ)
F.4. MOSAIC1176
The new approach is proposed formττ reconstruction using thematrix element basedmaximum likelihood.TheMatrix-elementOriented SAmplIngCalculator (MOSAIC) is similar technique to theMMC in termsof using likelihood function and probability density function. However there are a couple of differences.We firstly denote the likelihood definition:
L(mττ | pτ1µ , pτ2
µ , EmissT ) =
∫Ω
| M | 2 Pr(xττu |D) σ(mττ − mττ (xττu )) (5)
where pτ1µ , pτ2
µ are observed 4-momentum of each visible tau decay products,M is the amplitude for that1177
particular transition which is known from theory. xττu are unknown parameter sets for each τ lepton, Ω1178
is a volume in the xττu parameter space, subject to possible physical constrains. Pr(xττu |D) is posterior1179
probability according to unknown parameter sets xττu to observed result D in Bayesian statistics.1180
F.4.1. The Amplitude Calculation1181
As a ττ resonances, we can assume that three physics process can bee discussed. Z0, H0 and A0 can1182
decay into ττ final state.1183
9th May 2016 – 16:38 97
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
• Z0 is the Standard Model weak boson1184
• H0 is the (beyond) Standard Model Higgs boson with CP-even.1185
• A0 is the beyond Standard Model Higgs boson with CP-odd.1186
We can denote three amplitudes as following:1187
|M|2 ∝∑λ1,λ2
∑λ1,λ2
Pλ1λ2λ1λ2D1
λ1λ1D2
λ2λ2,Pλ1λ2
λ1λ2=
∑σ
Mλ1λ2σ (Mλ1λ2
σ )∗, Diλiλi=Mλi (Mλi )
∗ (6)
where P is the amplitude of tau pair production, D is the amplitude term of the decay of each tau lepton.λ1,2 are helicity state of each tau lepton and σ is initial particle helicity states. One of important thingin calculation of these amplitude is the spin correlations between the two taus. This correlation canautomatically take into account in Equation (6). In other words, there is no need for a particular simulationto get the transverse spin effects. We firstly denote the amplitude of production term, for Z0 boson andtwo Higgs boson reduced amplitude is:
Mλ1λ2σ (Z ) ∝
−gqσ
2[gτ+ + g
τ− + (gτ+ − g
τ−)λ β
](σλ + cosΘ) for λ1 , λ2
mλgqσ√
s(gτ+ + g
τ−) sinΘ for λ1 = λ2
,Mλ1λ2σ (H) ∝
βλ for H0
i for A0
The Z0 amplitude has two cases according to two tau helicity correlation. However, in case of λ1 = λ2 is1188
negligible because of√
s m. We reduce the propagator term in order to avoid bias from q2.1189
F.4.2. Tau Lepton Decay Amplitudes1190
The tau lepton decay summarise in Table 24, it can be divided by five mode.1191
In following section, we describe the tau decay density. In the method, an energy fraction between
Table 24: Summary of τ lepton decay mode.
Mode Decay BR(%)1p0n τ− → π−ντ 11.061p1n τ− → ρ−ντ → π−π0ντ 25.421pXn τ− → a−1 ντ → ρ0π−ντ → 2π0π−ντ 10.253p0n τ− → a−1 ντ → ρ−π0ντ → 2π−π+ντ 9.163pXn τ− → ωπ−ντ → 2π−π+π0ντ 4.80
1192
τ lepton and visible decay products x = Evis/Eτ are commonly used for both hadronic and leptonic1193
decay mode. For the leptonic decay the missing system invariant mass fraction b = mmis/mτ cannot be1194
neglected.We should be calculate with (x, b) plane.1195
Let’s start from the tau rest frame, we need to obtain information about invisible term of the τ lepton1196
decay, in other words missing system momentum and its direction. An equally good choice of parameters1197
is to replace the opening angle cos θ∗ with the energy fraction x, where θ∗ is the polar decay angle of the1198
visible decay products in the tau rest frame with respect to the polarization axis if the tau, which for a state1199
of definite helicity corresponds to the direction of flight in the laboratory frame.1200
9th May 2016 – 16:38 98
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
The relation between x and cos θ∗ can be obtained by solving for the visible energy Evis in the laboratoryframe, after a Lorentz boost from the rest frame:
cos θ∗ =Evis − γE∗visγ βp∗vis
, E∗vis =m2τ + m2
vis + m2mis
2mτ
where γ = Eτ/mτ, β =√
1 − 1/γ2, E∗vis and p∗vis are the energy and momentum of the visible decay1201
products in the tau rest frame. The energy and momentum in the rest frame are given by:1202
p∗vis =λ(m2
τ,m2vis,m
2mis)
1/2
2mτ(7)
where λ(a, b, c) = a2+ b2+ c2−2(ab+ bc+ ca). After substitution into Equation (F.4.2), we obtained:
cos θ∗ =2x − (1 + a2 + b2)√
λ(1, a2, b2)(1 − (xmτ/Evis)2), E∗vis =
mτ
2(1 + a2 + b2) (8)
where a, b = mvis/mτ,mmis/mτ are mass fraction of each tau decay products.1203
Finally in the MOSAIC calculation, we use1204
xu = (x, b, φ) (9)
where φ is angle specifying the orientation of the tau lepton momentum vector with respect to the1205
momentum vector of the visible decay products. Hence xττu for each decay mode are :1206
xττu =
(x1, x2, φ1, φ2) for had-had(x1, x2, φ1, φ2, b1) for lep-had(x1, x2, φ1, φ2, b1, b2) for lep-lep
(10)
F.4.3. ` mode1207
In terms of the parameters, the probability density functions for τ− → `− ν`ντ with a tau polarizationPτ = ±1, is given by
dΓdxdb
=bm3
τ
8β3
(2 − x
m2τ
E2`
(1 + a2 − b2))×
[(1 − a2)2 + b2 (1 + a2 − 2b2) +
Pτ (2x + (1 + a2 − b2)(1 − a2 − 2b2))β
]
(11)
where β =√
1 − (xmτ/E` )2, which has been obtained from [104] using the transformation of Equation (8).1208
The distributions for the two polarization states are shown in Figure 72 in the form of a density plot in the1209
(x, b) plane.1210
F.4.4. 1p0n mode1211
For the 1p0n mode τ− → π−ντ with tau polarization Pτ = ±1, the decay width differential in the poin x1212
fraction is given by [104]1213
dΓdx=
2 − x m2τ
E2π
(1 + a2)
(2 − 2a2) β3
[1 +
Pτ (2x − 1 − a2)(1 − a2) β
](12)
where β =√
1 − (xmτ/Eπ )2. Figure 73(a) black lines shows the mode matrix element of this 1p0nmode.1214
The solid(dashed) line show Pτ = +1(−1).1215
9th May 2016 – 16:38 99
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
(a) (b)
0.0 0.2 0.4 0.6 0.8 1.0
x=E`/Eτ
0.0
0.2
0.4
0.6
0.8
1.0
b=mνν/m
τ
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
0.0 0.2 0.4 0.6 0.8 1.0
x=E`/Eτ
0.0
0.2
0.4
0.6
0.8
1.0
b=mνν/m
τ
0.00
0.02
0.04
0.06
0.08
0.10
0.12
0.14
0.16
0.18
Figure 72: Probability density function of the visible energy fraction x and missing invariant mass fraction b in `mode. Left(right) plot shows Pτ = +1(−1) states. As a lepton both plots use muon and the energy of muon is30GeV.
F.4.5. Decay of Vector Meson1216
In the case of decay of vector meson, we should take into account which are longitudinally (L) ortransversely (T) polarised. In order to consider it, the decay widths are separately computed in [104] asHαv (x,m2) defined by following:
1BRΓ
dΓα
dx=
cos2 ω + a2 sin2 ω + Pτ cos2 ω + a sin 2ω tan θ − a2 sin2 ω)(1 − a2)(1 + 2a2)
(α = L)
sin2 ω + a2(1 + cos2 ω) + Pτ sin2 ω − a sin 2ω tan θ − a2(1 + cos2 ω)(1 − a2)(1 + 2a2)
(α = T )(13)
where BR and Γ are branching ratio and total decay width, hL, hT , cosω are given by
cosω =1 − a2 + (1 + a2) β cos θ√
((1 − a2) sin θ/γ)2 + (cos θ + β(1 + a2))2
From Equation (13), eliminate following variable θ, ω, β, γ, we obtained the probability density function.However, vector meson, i.e. ρ, a1, has non-zero mass width. Thus we should take into account mass widthgiven by
1BRΓ
dΓα
dx=
BRN
∫ xm2τ
(nmπ )2dm2Hα
v (x,m2)Fv (m2)
where n is the number of pion in final state. N, Fv (m2), Dv (m2), Γv (m2) are the normalisation factor, thevector resonance shape function, the vector meson propagator with invariant mass m2 and the runningwidth which defined by
Fv (m2) = (1 − a2)2(1 + 2a2)Dv (m2)2
fv (m2), N =∫ m2
τ
(nmπ )2dm2Fv (m2),
Dv (m2) =1
m2 − m2v + imΓv (m2)
, Γv (m2) = Γvm fv (m2)mv fv (m2
v)
9th May 2016 – 16:38 100
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
where fv is line shape factor:
fρ(m2) = (1 − 4m2π/m
2τ )3/2
fa1 (m2) =
4.1m2 (m2 − 9m2
π )[1 − 3.3(m2 − 9m2
π ) + 5.8(m2 − 9m2π )2
]for m2 < (mρ + m2
π )
1.623 +10.38
m2 −9.32m4 +
0.65m6 for m2 > (mρ + m2
π )
After integrate over dm2 space, we obtained the probability density function as shown in Figure 731217
Thus we can calculate the amplitude of the vector meson decay if we could know its polarization state.In order to get information of vector meson polarization state, we introduce helicity angle as polarizationanalyser referenced in [105]. In this reference, a combined decay width defined by
1BRΓ
dΓα
dx=
3(1 + Pτ )W+(θ, ψ) + 3(1 − Pτ )W−(θ, ψ)(m2
τ + 2m2)W±(θ, ψ) = w±0 (cos θ)hρ,a1
0 (cosψ) + w±1 (cos θ)hρ,a11 (cosψ)
where w±0,1 and h0,1 are
w+0 =(mτ cosω cos
θ
2+ m sinω sin
θ
2)2, hρ0 = 2 cos2 ψ
w−0 =(mτ cosω sin
θ
2− m sinω cos
θ
2)2, hρ1 = sin2 ψ
w+1 =(mτ sinω cos
θ
2− m cosω sin
θ
2)2+ m2 sin2 θ
2, ha1
0 = sin2 ψ
w−1 =(mτ sinω sin
θ
2+ m cosω cos
θ
2)2+ m2 cos2 θ
2, ha1
1 = (1 + cos2 ψ))/2
where cosψ is the spin analyser defined by following
cosψ =
m√m2 − 4m2
π
E1 − E2
| ~p1 + ~p2 |for ρ meson
8m2 ~p1 · ( ~p2 × ~p3)/| ~p1 + ~p2 + ~p3 |√−λ(λ3, λ2, λ1)
for a1 meson
where λ1,2,3 = λ( m2,m223,31,12,m
2π ), these amplitude should also be integrated with the line shape factor.1218
Thus, we obtained four 2-dimensional density as shown in Figure 73 (b-e).1219
F.4.6. Markov Chain Mote Carlo algorithms1220
The MOSAIC use the Markov Chain Monte Carlo (MCMC) as a parameters scan instead of a grid point1221
scan. The MCMC methods are a class of algorithms which are used for simulating samples from a1222
posterior distribution that has the desired true posterior distribution as its stationary distribution. The1223
Metropolis-Hastings algorithms is one of best algorithms to get Markov chain τ1, τ2, · · · , τt, · · · with1224
equilibrium distribution π(τi | X), where τi are parameter set at state i. Let q(τ∗ | τt ) be the proposal1225
density which is a function that depends on the current state ~τt ans a new proposed sample τ∗ . This1226
proposed values τ∗ is accepted as the next value τt+1 if a value αt ∈ U (0, 1) satisfies If the proposal is1227
9th May 2016 – 16:38 101
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
(a) (b) (c)
0.0 0.2 0.4 0.6 0.8 1.0
x=Eπ,ρ,a1/Eτ
0.0
0.1
0.2
0.3
0.4
0.5
1 Γτ
dΓα v
dx
π,Pτ= +1
a1,Pτ= +1 longitudinallya1,Pτ=−1 longitudinallya1,Pτ= +1 transversea1,Pτ=−1 transverse
π,Pτ=−1
ρ,Pτ= +1 longitudinallyρ,Pτ=−1 longitudinallyρ,Pτ= +1 transverseρ,Pτ=−1 transverse
0.0 0.2 0.4 0.6 0.8 1.0
x=Eρ/Eτ
0.0
0.2
0.4
0.6
0.8
1.0
Eπ∓/E
ρ
0.000.040.080.120.160.200.240.280.320.36
0.0 0.2 0.4 0.6 0.8 1.0
x=Eρ/Eτ
0.000
0.024
0.048
0.072
0.096
0.120
0.144
(d) (e)
0.0 0.2 0.4 0.6 0.8 1.0
x=Ea1/Eτ
1.0
0.5
0.0
0.5
1.0
cosψ
0.0000.0160.0320.0480.0640.0800.0960.1120.1280.144
0.0 0.2 0.4 0.6 0.8 1.0
x=Ea1/Eτ
0.000.040.080.120.160.200.240.280.320.36
Figure 73: Probability density function of the visible energy fraction x with non-zero mass width. Blue(red)distribution shows ρ(a1) meson. The solid(dot) line shows Pτ = ±1 in transverse polarised tau and the dashed(dash-dot) line shows Pτ = ±1 in transversely polarised tau. Left(right) shows zero(non-zero) mass width calculation.
not accepted, then τt+1 = τt . That is, the chain remains in its current state in time t + 1. The proposal1228
function might generate new values of a parameter that are accepted with very low probability, thus the1229
parameter will stay in the same state for long time periods before moving. Such chain has very strong1230
autocorrelation. Therefore, we need to do thinning that described after this sub-section. The sampling1231
points from the MCMC has to be checked a convergence, an autocorrelation and burn-in period.1232
Autocorrelation The MH algorithm has a strong autocorrelation within the chain. The k-lag autocor-relation ρk is the correlation between every draw and its kth lag given by:
ρk =
∑n−ki=1 (θi − θ)(θi+k − θ)∑n
i=1(θi − θ)2
In order to reduce the autocorrelation, the MOSAIC algorithm use sampling points every optimal ACF1233
k-lag.1234
Burn-in period The MCMC has a period where has strong effect from initial values, so-called burn-inperiod, should be removed from the chain. To estimate optimal burn-in size, the Effective Sample Size(ESS) are used in the MOSAIC algorithm given by following:
ESS(m) =n
1 + 2∑∞
k=1 ρk (m), ρk (m) =
∑n−ki=1+m(θi − x)(θi+k − θ)∑n
i=1+m(θi − θ)2
where ρk is the autocorrelation as a function of k-lag and burn-in period m. The optimal burn-in period1235
is size m which make the ESS maximum.1236
9th May 2016 – 16:38 102
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
Estimating Convergence To checking convergence of the sampling is important. In the MOSAICsapling, the chains runs in parallel. All the chains must have reasonably same results. The Gelman &Rubin method for checking convergence is
B =n
N − 1
N∑j=1
(θ j − ¯θ)2,W =1
N (n − 1)
N∑j=1
n∑i=1
(θi j − θ j )2, Var(θ) = (1 −1n
)W +Bn, R =
√Var(θ)
W
where B,W are between and within variance, Var(θ) is combined variance. If it satisfy R < 1.01 then it1237
converged.1238
G. Final Discriminant Studies1239
G.1. MSSM Higgs search1240
The results of this search are extracted from a binned likelihood function constructed from themττ invariant1241
mass distribution, as explained in Section 8. Different mττ mass reconstruction have been evaluated in this1242
search: the visible mass mvis, mtotT , the Missing Mass Calculator mMMC and Mosaic mττ . The invariant1243
mass reconstruction algorithms are described in Appendix F. Their performance has been evaluated using1244
the figure of merit defined by Asimov’s formula [101] given as1245
Z =
√2((s + b)ln
(1 +
sb
)− s
), (14)
where b is the background expectation for 3.21 fb−1and s is the signal expectation for the different1246
mass points. The results of the study are summarised in Table 25. For high mass signal samples, mtotT1247
performance is significantly better than the rest of mass reconstruction algorithms. For lower mass signal1248
samples, mtotT , Mosaic and MMC algorithms have similar performance. Even if Mosaic and MMC are1249
able to reconstruct with more accuracy the peak position of the signal, the mtotT variable achieves a better1250
separation between the multi-jet background and the signal. For this reason, the mtotT has been chosen as1251
discriminant variable in the statistical analysis of this search.1252
Mass Point mtotT mMMC Mosaic mvis
H/A 200 GeV 0.003 0.010 0.006 0.007H/A 300 GeV 0.183 0.266 0.252 0.266H/A 500 GeV 5.078 4.827 4.068 4.119H/A 600 GeV 7.179 6.125 5.256 5.300H/A 700 GeV 8.625 6.937 6.046 6.209H/A 800 GeV 9.875 7.986 6.734 6.886H/A 900 GeV 10.101 9.018 7.566 7.732
Table 25: Statistical significance of the different mass reconstruction algorithms as a function of the signal masspoint. The numbers correspond to an integrated luminosity of 3.21 fb−1and a conventional signal cross-section of1 pb−1.
9th May 2016 – 16:38 103
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
G.2. Optimisation of the b-tag category definition1253
The definition of the b-tag and b-veto categories is based on the identification of of least 1 jet of the event1254
as a b-jet. The choice of the jets to be considered in the definition of the categories has been optimised1255
based on the figure of merit of the binned statistical significance of the mtotT distribution. The significance1256
is calculated using the Asimov’s formula defined in Appendix G.1. The following options have been1257
considered in the optimisation:1258
• Event is selected for the b-tag category if the leading jet is tagged.1259
1260
• Event is selected for the b-tag category if the leading or sub-leading jets is tagged.1261
1262
• Event is selected for the b-tag category if any jet in the event is tagged1263
1264
In all cases, the jets must fulfil the requirement of pT > 25GeV. Table 26 shows the combined statistical1265
significance of the b-tag and b-veto categories for the different category definition options. Based on this1266
study, events are selected for the b-tag category if any jet in the event is identified as a b-jet.1267
Combined significance of the b-tag and b-veto categoriesMass Point Leading jet Lead. or sub-lead. jet Any jetH/A 300 GeV 2.20 2.50 2.60H/A 500 GeV 13.1 13.8 14.0H/A 600 GeV 2.16 2.18 2.19H/A 700 GeV 2.91 2.93 2.93H/A 800 GeV 3.65 3.66 3.66H/A 1000 GeV 4.77 4.77 4.77
Table 26: Statistical significance of the different options for the definition of the b-tag category as a function of thesignal mass point. The numbers correspond to an integrated luminosity of 3.21 fb−1and a conventional total signalcross-section of 1 pb−1.
G.3. Z′ → ττ search1268
A scan over lower thresholds on mtotT is performed in the range between 400 GeV and 900 GeV evaluating1269
the significance 14 for each masspoint. The results are depicted in Figure 74. The white semi-transparent1270
line indicates mass thresholds yielding largest significance for each masspoint under the requirement that1271
there is at least one expected background event, which is ensured for mass thresholds up to 800 GeV.1272
9th May 2016 – 16:38 104
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
sign
ifica
nce
Z0.20.3
1
23
10
2030
[TeV]Z'm
0.5000.6000.700 0.8000.900 1.0001.250 1.5001.750 2.0002.2502.500
thre
shol
dto
tT
m
400
450
500
550
600
650
700
750
800
850
900
36.5
934
.91
28.8
322
.33
16.7
912
.56
5.75
2.69
1.20
0.58
0.28
0.14
22.8
1
30.1
828
.13
22.8
717
.66
13.7
46.
703.
261.
500.
740.
360.
18
9.16
22.5
725
.34
22.2
617
.92
14.3
97.
483.
781.
800.
910.
440.
22
2.31
14.1
1
20.9
820
.95
17.4
914
.56
8.06
4.29
2.11
1.08
0.54
0.27
1.14 5.
2615
.86
17.8
816
.13
14.1
48.
304.
532.
311.
210.
610.
31
0.78
2.15
9.92
14.5
214
.76
13.5
38.
564.
892.
571.
380.
710.
37
0.57
1.07
4.15
10.8
712
.81
12.4
68.
535.
052.
761.
530.
800.
42
0.47
0.68
1.71
7.12
10.3
711
.41
8.50
5.26
2.98
1.71
0.92
0.49
0.36
0.50
0.94
3.26
7.78
9.68
8.08
5.26
3.05
1.80
0.98
0.54
0.28
0.38
0.51
1.55
4.85
7.66
7.50
5.17
3.08
1.85
1.03
0.57
0.22
0.29
0.35
0.62
2.40
5.24
6.74
4.99
3.01
1.87
1.06
0.60
Figure 74: Significance computed using Equation 14 for each Z ′ masspoint for various lower thresholds on the totaltransverse mass mtot
T . The white semi-transparent line indicates thresholds providing the largest significance.
9th May 2016 – 16:38 105
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
H. mT(τ1, EmissT
) mismodelling studies1273
H.1. Motivation1274
A mismodelling in the mT(τ1, EmissT ) distribution in b-veto category for OS region is observed (as can be1275
seen in Figure 7 (d) and it is reproduced here in Figure 75 (a) ). The mismodelling only appears in b-veto1276
OS (a) and it has also a reflection in mtotT distribution. However, the SS region of the b-veto category1277
does not show any disagreement, neither for mT(τ1, EmissT ) (Figure 75 (b)) nor mtot
T . This feature was not1278
observed in the same plot for EOYE CONF NOTE (Figure 75 (c)) [106].1279
1280
This disagreement raised concerns about the validity of the background model, so several studies were1281
performed in order to figure out the reason of the disagreement.1282
1283
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(a)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310
410 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310
410=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
Figure 75: mT(τ1, EmissT ) for: (a) current b-veto OS, showing the mismodelling (b) current b-veto SS showing a good
agreement, (c) EOYE plot, showing good agreement
H.2. Studies1284
Since the mT variable depends directly of the ∆φ angle between the objects, the angular distributions1285
(∆φ, ∆R) between both τ and EmissT in b-veto category for SS and OS regions were checked to find1286
any mismodelling that could explain the behaviour of mT plot. For this, the current analysis cut on ∆φ1287
(∆φ > 2.7) was removed.1288
As it is observed in figures 76 and 77, there is a good general agreement between data and background1289
for all the distributions. Especially in SS region (figure 77), that has higher statistics, data points show1290
almost no deviation from the background prediction. In OS region (figure 76), with significantly less1291
events, data points fluctuate more. However, there is not trace of a general mismodelling, rather than1292
statistical fluctuations. Most points are within the error bands and so, due to the lack of statistics, no1293
strong conclusion can be reached.1294
1295
9th May 2016 – 16:38 106
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
)missTE,0τ)(φ(∆
Eve
nts/
0 G
eV
5
10
15
20
25
30
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
)missTE,0τ)(φ(∆
0 0.5 1 1.5 2 2.5 3Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(a)
)missTE,1τ)(φ(∆
Eve
nts/
0 G
eV
10
20
30
40
50=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
)missTE,1τ)(φ(∆
0 0.5 1 1.5 2 2.5 3Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
missT
E0,τ R∆
Eve
nts/
0.2
5
10
15
20
25 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
miss
TE0,τ R∆
0 0.5 1 1.5 2 2.5 3 3.5 4Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
missT
E1,τ R∆
Eve
nts/
0.2
5
10
15
20
25 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
miss
TE1,τ R∆
0 0.5 1 1.5 2 2.5 3 3.5 4Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
Figure 76: Angular distributions for b-veto OS: (a) ∆φ(τ0, EmissT ), (b) ∆φ(τ1, Emiss
T ), (c) ∆R(τ0, EmissT ), (d)
∆R(τ1, EmissT ).
Since the angular distributions did not show any mismodelling that could be related to the mismodelling1296
in mT(τ1, EmissT ), the main changes from EOYE analysis were revised in order to see if the disagreement1297
was introduced later. Two main changes were reverted, in separately studies: first, the plots were redone1298
using the Fake Factors computed at EOYE time and, second, the leading τ pT cut was changed back from1299
110 GeV (current threshold) to 135 GeV (EOYE threshold). Neither of them, however, was conclusive.1300
For a correct comparison with respect to EOYE selection, current plots had to be done in the inclusive1301
category, before the b-tagging cut, as this cut was not present at EOYE.1302
1303
The result of the first test, comparing plots with different Fake Factors (from EOYE time and current1304
values) is shown in figure 78. The conclusion is that the change in the FF value has very little effect in the1305
final distribution. Both figures are practically identical, so updating the FF cannot have been the reason1306
of the mismodelling in mT(τ1, EmissT ).1307
9th May 2016 – 16:38 107
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
)missTE,0τ)(φ(∆
Eve
nts/
0 G
eV
20
40
60
80
100
120
140
160=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
)missTE,0τ)(φ(∆
0 0.5 1 1.5 2 2.5 3Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(a)
)missTE,1τ)(φ(∆
Eve
nts/
0 G
eV
20
40
60
80
100
120
140=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
)missTE,1τ)(φ(∆
0 0.5 1 1.5 2 2.5 3Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
missT
E0,τ R∆
Eve
nts/
0.2
20
40
60
80
100 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
miss
TE0,τ R∆
0 0.5 1 1.5 2 2.5 3 3.5 4Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
missT
E1,τ R∆
Eve
nts/
0.2
10
20
30
40
50
60
70 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 3.21 fbs
hadτhadτ→H/ASame-sign CR
miss
TE1,τ R∆
0 0.5 1 1.5 2 2.5 3 3.5 4Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
Figure 77: Angular distributions for b-veto SS: (a) ∆φ(τ0, EmissT ), (b) ∆φ(τ1, Emiss
T ), (c) ∆R(τ0, EmissT ), (d)
∆R(τ1, EmissT ).
1308
The result of the second test, changing back the leading τ pT cut from 110 GeV to 135 GeV, is shown in1309
figure 79. This change indeed has a visible effect, mainly in matter of statistics. The threshold set for the1310
EOYE was tighter, and so, less events made to the final plots. The shape of the plot is not significantly1311
altered, but the statistical error of the data points and background prediction, depending directly of the1312
number of events passing the selection, is increased. Due to the bigger errors, data and background seem1313
more compatible.1314
1315
However, there is a another subtle difference between the EOYE plot and the current one that has to be1316
taken into account: the luminosity. Figure 75 compared two plots with significantly different amount of1317
data: EOYE plot is fully unblinded (3.21 fb−1) but the current plot is only shown for the first 0.4 fb−1of1318
data, since the analysis was blinded again. In order to compare the plots consistently, the EOYE plot was1319
9th May 2016 – 16:38 108
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
re-blinded for the same 0.4 fb−1 of data. The comparison between those plots is shown in figure 80 and1320
in this, the reblinded EOYE plot shows a similar mismodelling as the one being studied. The pattern is1321
not exactly the same in all points the there is a big similarity between both shapes. This mismodelling1322
was not seen in previous studies because the EOYE plot, due to the tighter leading τ pT cut, has larger1323
error bands (both for data and background) that makes the disagreement less evident. A direct comparison1324
of both plots show, however, that they have similar shapes and themismodelling is consistent between them.1325
1326
H.3. Conclusion1327
This result points to the mismodelling being a statistical fluctuation that appears in the first part of the1328
dataset. This is based in the fact that reblinding the EOYE plot to the current allowed luminosity shows1329
a similar mismodelling and none of the studies of angular distributions or recent changes in the analysis1330
(FF, pT cut) could give a satisfactory explanation of the disagreement. None of them, indeed, showed any1331
clear mismodelling, more than statistical fluctuations within the error band. The fact that, at the time of1332
EOYE, the cuts were tighter and hence, the error bands were wider, made the mismodelling not so evident.1333
After fully unblinding the EOYE plot, any trace of the mismodelling disappeared and the agreement of1334
the plot improved.1335
9th May 2016 – 16:38 109
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
) [GeV]missTE,0τ (Tm
Eve
nts/
20
GeV
2
4
6
8
10
12
14
16
18 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,0τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(a)
) [GeV]missTE,0τ (Tm
Eve
nts/
20
GeV
2
4
6
8
10
12
14
16
18 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,0τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
5
10
15
20
25
30
35
40
45=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
5
10
15
20
25
30
35
40
45=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
[GeV]TotTm
Eve
nts/
GeV
0.2
0.4
0.6
0.8
1=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TotTm
Eve
nts/
GeV
0.2
0.4
0.6
0.8
1=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(f)
Figure 78: Comparison of transverse mass variables using different FakeFactors, current numbers on the left column,FakeFactors for EOYE on the right column, for inclusive SS: (a) mT(τ0, Emiss
T ), (b) mT(τ0, EmissT ) with EOYE FF, (c)
mT(τ1, EmissT ) , (d) mT(τ1, Emiss
T ) with EOYE FF, (e) mtotT , (f) mtot
T with EOYE FF
9th May 2016 – 16:38 110
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
) [GeV]missTE,0τ (Tm
Eve
nts/
20
GeV
2
4
6
8
10
12
14
16
18 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,0τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(a)
) [GeV]missTE,0τ (Tm
Eve
nts/
20
GeV
2
4
6
8
10
12
14=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,0τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
5
10
15
20
25
30
35
40
45=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
24
68
101214
1618
2022
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
[GeV]TotTm
Eve
nts/
GeV
0.2
0.4
0.6
0.8
1=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(e)
[GeV]TotTm
Eve
nts/
GeV
0.05
0.1
0.15
0.2
0.25
0.3
0.35
0.4
0.45 =400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(f)
Figure 79: Comparison of transverse mass variables using different threshold in leading τ pT cut, 110 GeV (current)on the left column, 135 GeV (EOYE threshold) on the right column: (a) mT(τ0, Emiss
T ) 110 GeV, (b) mT(τ0, EmissT )
135 GeV, (c) mT(τ1, EmissT ) 110 GeV, (d) mT(τ1, Emiss
T ) 135 GeV, (e) mtotT 110 GeV, (f) mtot
T 135 GeV
9th May 2016 – 16:38 111
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(a)
) [GeV]missTE,1τ (Tm
Eve
nts/
20
GeV
1−10
1
10
210
310=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
) [GeV]missTE,1τ (Tm
0 20 40 60 80 100 120 140 160 180 200Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(b)
[GeV]TotTm
Eve
nts/
GeV
3−10
2−10
1−10
1
10
=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(c)
[GeV]TotTm
Eve
nts/
GeV
3−10
2−10
1−10
1
10=400 GeV Am =500 GeV Am=1000 GeV Am Multi-jet
+jetsττ→Z +jetsντ→W+single-toptt Others
Data Bkg. uncert.
-1=13 TeV, 0.41 fbs
hadτhadτ→H/APre-fit
[GeV]TotTm
0 100 200 300 400 500 600 700 800 900 1000Dat
a/B
kg R
atio
0.20.40.60.8
11.21.41.61.8
(d)
Figure 80: mT(τ1, EmissT ) for: (a) current inclusive OS (b) EOYE reblinded to 0.4 fb−1
9th May 2016 – 16:38 112
Not
revi
ewed
,for
inte
rnal
circ
ulat
ion
only
DRAFT
List of contributions1336
Alvarez Piqueras, Damian Editor, Ntuple production, mass reconstruction sensitivity, fake fac-tor studies, multijet control region studies.
Beckingham, Matthew LepHad Channel, trigger studies.Blumenschein, Ulrike xTau framework and derivations.Davey, Will Tau systematics, high pT taus, background estimation.Drechsler, Eric xTau frameworkDuschinger, Dirk Z ′ → ττ search (HadHad channel), Z ′ → ττ combination, TauA-
nalysisTools developer.Fiorini, Luca Fake factor optimisation and systematics, editing of the note, Same
sign region studies, pre-fit plots, Supervisor of Damian Alvarez.Goussiou, Anna Supervisor, LepHad Channel.Gwilliam, Carl HBSM convenor, post-fit plots.Hamity, Guillermo Nicolas Detector systematics studies, editing of the note.Hauswald, Lorenz Editor, Fake rates and systematics, bbH signal validation, derivation
definition, W+jets corrections and systematics, theory systematics,limit.
Hyneman, Rachel LepHad Channel, Z ′ → ττ searchJabbar, Samina b-associated production signal studies.Koneke, Karsten Supervisor, LepHad Channel.Liu, Hao LepHad Channel, gluon fusion acceptance uncertainties.Mader, Wolfgang Supervisor.McCarn, Allison HBSM convenor, LepHad Channel, combination.Moore, Roger Supervisor.Mori, Tatsuya Tau systematics studies.Morinaga, Masahiro LepHad Channel, Mass reconstruction.Neubauer, Mark Supervisor.Pakela, Julia LepHad Channel.Pickering, Mark Andrew cutflows, ntuple production, high pT tau studies, trigger studies,
editing of the note.Pranko, Aliaksandr Mass reconstruction studies.Rompotis, Nikolaos LepHad Channel, combination.Sales De Bruin, PedroHenrique
LepHad Channel, xTau framework.
Schwarz, Thomas Andrew Supervisor, LepHad Channel, editor of the conference note.Straessner, Arno Supervisor.Tanaka, Junichi Supervisor, LepHad Channel.Vickey, Trevor Supervisor.Zhang, Lei LepHad Channel.Zinonos, Zinonas xTau framework and derivations.
1337
1338
9th May 2016 – 16:38 113