Post on 18-Jan-2018
description
WW benchmark analysis: Progress report
Ron Cassell, Tim Barklow8/4/11
1
Event Sample
• Start with 10000 each w34974, w34975 (uddu events, alpha=0, 100% polarization)
• End with 315 + 618 full energy WW and ZZ events.
• 933 evts reduced to 901 by reconstruction cuts.
• Where do they go?
2
Event accountingw34974 Generated Eevt>995. cosΘmx<.97 cosΘmx<.90
WW 7808 1994 506 308
ZZ 127 40 10 7
uDdU 1968
γZ 90
unknown 7
w34975 Generated Eevt>995. cosΘmx<.97 cosΘmx<.90
WW 1890 376 373 357
ZZ 4628 1229 401 261
uDdU 527
γZ 2935
unknown 20
3
“Perfect” reconstruction• Find pdg94 particles. If n != 2, fail.• Find parent quarks. If n != 2, only use quarks with
1 daughter. If n still != 2, fail.• Trace generator final state particles to pdg94.• Boost quarks and fs particles to pdg94 system,
then attach fs particles to nearest q.• Jet 0 is max E jet in dijet with max cos(Θ), jet 1
partner, jet 2 maxE in other dijet, jet 3 partner• Should be no difference in jet 0,2 distributions or
jet 1,3 distributions
4
Jet clustering from PFOs
• Hemisphere cut: Use thrust axis, separate particles by dot product >< 0.
• For each hemisphere: Boost to cm, find thrust axis, separate into hemisphere.
• If # particles in any of the 4 jets < 2, fail.• Match to “perfect” with chisq.
5
Jet energy offsets and resolution
6
dE m90 (GeV)
Jet Energy (GeV)0 100 200 300 400 500
-35
-30
-25
-20
-15
-10
-5
0
5
WW1000: Jet energy pedestals
dE/E(rms90)
Jet Energy (GeV)0 100 200 300 400 500
0.04
0.05
0.06
0.07
0.08
0.09
0.10
0.11
WW1000Fixed E qq
Jet Energy resolution
Procedure
• Use the matched jets to find the errors in the 16 variables. (E,β,Θ,φ for each jet)
• Not enough events for meaningful correlations in the covariance matrix, use diagonal for now.
• Constrain ΣE = 1000, ΣPx = ΣPy = ΣPz = 0.• Motivation: Tim’s fast MC study of ZH at 350
GeV
7
jet
jet
E0.3
E
jet
jet
E0.3
E
Reconstructed Mbb 4C Fitted Mbb
0.4
0.5 0.6
0.4
0.5 0.6
e e ZH qqbb
Mbb (GeV) Mbb (GeV) Mbb (GeV) Mbb (GeV)
8
1
350
500
s GeV
L fb
jet
jet
42 MeV
E0.3
E
hM
e e ZH
qqbb
jet
jet
46 MeV
E0.4
E
hM
jet
jet
48 MeV
E0.5
E
hM
jet
jet
50 MeV
E0.6
E
hM
Mbb (GeV) Mbb (GeV)
Mbb (GeV) Mbb (GeV)
9
Prefit results: Energy
10
entries/2 GeV
delta Energy (GeV)-60 -40 -20 0 20 40 60
020406080
100120140160180200220240
Original Recon/LE jet delta Energy Entries : 1802 Mean : 0.27646 Rms : 19.526
gauss amplitude : 156.48±6.111 mean : 0.98274±0.2029 sigma : 8.0574±0.241 χ² : 3.7144
Recon-perfect LE jet energyentries/4 GeV
delta jet energy (GeV)-100 -50 0 50 1000
20
40
60
80
100
120
140
160
180
Original Recon/HE jet delta Energy Entries : 1802 Mean : -9.4062 Rms : 28.060
gauss amplitude : 133.53±4.890 mean : -8.7756±0.5237 sigma : 19.658±0.533 χ² : 3.0654
recon-perfect HE jet energy
Prefit results: Beta
11
entries/.0001
delta Beta-0.004 -0.002 0.000 0.002 0.004
0
50
100
150
200
250
300 Original Recon/HE jet delta Beta Entries : 1802 Mean : -2.9699E-4 Rms : 1.5094E-3
gauss amplitude : 187.65±7.772 mean : -1.0842E-4±9.220E-6 sigma : 3.0525E-4±9.64E-6 χ² : 4.4478
HE jet delta Beta
entries/.001
delta Beta-0.04 -0.02 0.00 0.02 0.04
0
50
100
150
200
250
300Original Recon/LE jet delta Beta Entries : 1802 Mean : -3.1391E-3 Rms : 0.018282
gauss amplitude : 154.79±8.801 mean : -2.0286E-3±1.260E-4 sigma : 3.1054E-3±1.524E-4 χ² : 6.5475
LE jet delta Beta
Prefit results: Theta
12
entries/2mr
delta Theta-0.10 -0.05 0.00 0.05 0.100
50
100
150
200
250
300
350Original Recon/HE jet delta Theta Entries : 1802 Mean : -3.3525E-6 Rms : 0.021391
gauss amplitude : 219.58±9.316 mean : 3.6259E-4±1.4178E-4 sigma : 5.5268E-3±1.868E-4 χ² : 4.5346
HE jet: delta Theta
entries/10mr
delta Theta-0.3 -0.2 -0.1 0.0 0.1 0.2 0.3
0
100
200
300
400
500
600Original Recon/LE jet delta Theta Entries : 1802 Mean : 1.0540E-3 Rms : 0.051611
gauss amplitude : 471.45±21.21 mean : -9.8352E-4±3.2583E-4 sigma : 0.012500±4.580E-4 χ² : 6.3549
LE jet: delta Theta
Prefit results: Phi
13
en tries/5mr
delta Phi-0.15 -0.10 -0.05 0.00 0.05 0.10 0.150
100
200
300
400
500
600
Original Recon/HE jet delta Phi Entries : 1802 Mean : 2.8874E-4 Rms : 0.028195
gauss amplitude : 487.19±19.47 mean : 2.1075E-5±1.6378E-4 sigma : 6.4997E-3±0.000202 χ² : 5.4186
HE jet: delta Phi
entries/10mr
delta Phi-0.4 -0.3 -0.2 -0.1 0.0 0.1 0.2 0.3 0.4
0
50
100
150
200
250
300
350
400
450
500Original Recon/LE jet delta Phi Entries : 1802 Mean : -3.1945E-3 Rms : 0.067029
gauss amplitude : 453.23±12.8 mean : -7.1323E-4±3.3798E-4 sigma : 0.012975±0.000142 χ² : 5.5149
LE jet: delta Phi
Prefit results: Mass
14
entries/1 GeV
delta Mass (GeV)-30 -20 -10 0 10 20 30
0
10
20
30
40
50
60
70
80
90
100
110
120
130
140
150
160
Original Recon/Dijet/Recon-Perfect/dDijet M Entries : 1802 Mean : 2.0673 Rms : 6.9359
gauss amplitude : 113.15±3.821 mean : 1.9154±0.1507 sigma : 6.0400±0.143 χ² : 1.6616
Reconstructed - Generated dijet Mass
Observations
• Offset in Energy expected.• Offset in Beta unexpected.• Offset in Mass opposite to what I expected.
15
4C fit results
16
entries/0.2 GeV
(Fit-Generated) dijet Momentum (GeV)-4 -3 -2 -1 0 1 2 3 4
0
20
40
60
80
100
120
140
160
180
200
Original Recon FitD0/Dijet/Recon-Perfect/dDijet P Entries : 1802 Mean : -0.088457 Rms : 1.0859
gauss amplitude : 150.92±5.052 mean : -0.17692±0.02216 sigma : 0.89385±0.0206 χ² : 2.8588
4CFit: delta dijet Momentum
entries/0.1 GeV
(Fit-Generated) dijet Energy (GeV)-4 -2 0 2 4 6
0
20
40
60
80
100
120
140
160
180
200
Original Recon FitD0/Dijet/Recon-Perfect/dDijet E Entries : 1802 Mean : 0.55217 Rms : 1.1678
gauss amplitude : 144.00±5.015 mean : 0.43481±0.02529 sigma : 0.91193±0.0224 χ² : 3.5472
4CFit: delta dijet Energy
4C fit results
17
entries/1 GeV
(Fit-Generated) dijet Mass (GeV)-40 -30 -20 -10 0 10 20 30
0
20
40
60
80
100
120
140
160
180
200
Original Recon FitD0/Dijet/Recon-Perfect/dDijet M Entries : 1802 Mean : 3.5614 Rms : 5.9782
gauss amplitude : 144.97±5.177 mean : 3.3153±0.1270 sigma : 4.5212±0.117 χ² : 3.0733
4CFit: delta dijet Mass
Comments
• Not the improvement we expected• Trying to understand:• Mass offset, beta offset.• If mass errors make sense.• To check fits, input correct beta values.
18
Fit check
19
entries/1 GeV
delta Mass (GeV)-40 -20 0 20 40 60
0
50
100
150
200
250
300
Original Recon FitD2/Dijet/Recon-Perfect/dDijet M Entries : 1802 Mean : 0.89276 Rms : 5.8289
gauss amplitude : 222.95±8.411 mean : 0.59359±0.07219 sigma : 2.8959±0.0822 χ² : 3.4637
4CFit:correct beta input: delta Mass
Mass error checks• Can write out the full error propagation for dijet
mass.• If we use mean values of the perfect
distributions, and gaussian fits for the deltas, substituting these values gives ΔM/M = 7.4%. We measure 7.35%.
• The breakdown: from ΔE: 5.4%, Δangles: 3.4%, Δβ: 3.7%
• The constraints eliminate the ΔE error, but broaden slightly the other errors.
• Should get to 5% after fit, but see 5.4%.
20
Next steps
• 100k of each polarization generated, need to process.
• Should allow full covariance matrix calculation• Need to understand “low β” in reconstruction.
21
Backups
22
Jet Energy
23
Jet Energy (GeV)0 100 200 300 400 500
0
20
40
60
80
100
120
140
160
180
HE jet EnergyLE jet Energy LE jet Energy
Entries : 1802 Mean : 140.45 Rms : 65.556
HE jet Energy Entries : 1802 Mean : 358.99 Rms : 65.599
Perfect Recon: Jet Energy
Jet Energy (GeV)0 100 200 300 400 500
0
20
40
60
80
100
120
140
160
180
HE jet EnergyLE jet Energy
LE jet Energy Entries : 1802 Mean : 140.72 Rms : 65.266
HE jet Energy Entries : 1802 Mean : 349.59 Rms : 62.505
Original Recon: Jet Energy
Jet Beta
24
entries/.0005
Beta0.980 0.985 0.990 0.995 1.0000
100
200
300
400
500
600
700
Entries : 1802 Mean : 0.99876 Rms : 1.7389E-3
Perfect Recon/HE jet Beta
entries/.005
Beta0.6 0.7 0.8 0.9 1.0
0
100
200
300
400
500
600
700
800
900
Entries : 1802 Mean : 0.98114 Rms : 0.041318
Perfect Recon/LE jet Beta
25
65 70 75 80 85 90 95 100 10565
70
75
80
85
90
95
100
105
Original Recon Fit0/Dijet/Recon/Dijet M2 vs M1
26
75 80 85 90 95
74
76
78
80
82
84
86
88
90
92
94
96
98
100
Original Recon Fit0/Dijet/Perfect/Dijet M2 vs M1