New Physics Searches with bs+- Transitions and Rare Decays ... · B+ !K+ + B ! + + B ! + B !˝+˝...

B+ → K+µ+µ− B → µ+µ−µ+µ− B → µ+µ− B → τ+τ−

New Physics Searches with b → s`+`− Transitionsand Rare Decays at LHCb

Kristof De BruynOn behalf of the LHCb Collaboration

XXXI Rencontres de Physique de la Vallee d’AosteLa Thuile – March 8th, 2017

Kristof De Bruyn (CPPM) b → s`+`− and Rare Decays at LHCb La Thuile 2017 1 / 31


b → s`+`− Transitions and Rare Decays

Standard Model

B0s

s

b

u, c, t

u, c, t

Wγ, Z0

ℓ−

ℓ+

B0s

s

b

u, c, t ν

ℓ−

ℓ+

W

W

I Flavour Changing Neutral Current

I Forbidden at Tree level

⇒ Loop suppressed

I Sensitive to new physics contributions

Beyond the SM Theories

I Z ′/W ′ models, leptoquarks, 2HDM, . . .

B0s

s

b

Z ′

ℓ−

ℓ+

B0s

s

b

X+

W−

tX0

ℓ−

ℓ+

B0s

s

b

u, c, t ν

ℓ−

ℓ+

W

X



Puzzling Tensions in b → s`+`− Transitions

B0 → D(∗)−τ+ντ

I R(D(∗)) = B(B0→D(∗)−τ+ντ )

B(B0→D(∗)−µ+ντ )

R(D)0.2 0.3 0.4 0.5 0.6

R(D

*)

0.2

0.25

0.3

0.35

0.4

0.45

0.5BaBar, PRL109,101802(2012)Belle, PRD92,072014(2015)

LHCb, PRL115,111803(2015)

Belle, PRD94,072007(2016)

Belle, arXiv:1608.06391

Average

SM Predictions

= 1.0 contours2χ∆

R(D)=0.300(8) HPQCD (2015)R(D)=0.299(11) FNAL/MILC (2015)R(D*)=0.252(3) S. Fajfer et al. (2012)

HFAG

Summer 2016

) = 70%2χP(

HFAGSummer 2016

HFAG, arxiv:1612.07233

B+ → K+`+`−

I RK = B(B+→K+µ+µ−)

B(B+→K+e+e−)

]4c/2 [GeV2q0 5 10 15 20

KR

0

0.5

1

1.5

2

SM

LHCbLHCb

LHCb BaBar Belle

LHCb, PRL 113 (2014) 151601, arxiv:1406.6482

B0 → K∗0µ+µ−

I Angular Observable P ′5

]4c/2 [GeV2q0 5 10 15

5'P

-2

-1

0

1

2LHCb

SM from DHMV

LHCb, JHEP02 (2016) 104, arxiv:1512.04442

B+ → K+µ+µ−

I Differential branching fraction

]4c/2 [GeV2q0 5 10 15 20

]2/G

eV4 c ×

-8 [

102 q

/dBd 0

1

2

3

4

5

LCSR Lattice Data

LHCb

−µ+µ+ K→+B

LHCb, JHEP06 (2014) 133, arxiv:1403.8044Kristof De Bruyn (CPPM) b → s`+`− and Rare Decays at LHCb La Thuile 2017 3 / 31

http://arxiv.org/abs/1612.07233





Hints for New Physics?

I Model-independent approach:Effective Hamiltonian

I Best fit model has Wilson coefficientCNP

9 ≈ −1 (4 to 5σ)I What can explain this?

1 Statistical fluctuations

2 Not-yet-understood SM effects

3 New Physics

This Talk

1 Phase difference in B+ → K+µ+µ−

2 Search for B0s → µ+µ−µ+µ−

3 B(B0s → µ+µ−) & Lifetime ← New!

4 Search for B0s → τ+τ− ← New!

In AdditionI Talk on LFU tests at LHCb

[Stefanie Reichert, Wednesday 16h50]

I YSF talk on Λ0b → pπ−µ+µ−

[Eluned Smith, Tuesday 18h05]

Branching Ratios

Angular Observables HPiLAll

-3 -2 -1 0 1 2 3

-3

-2

-1

0

1

2

3

C9NP

C10

NP

S.Descotes-Genon et al., JHEP 06 (2016) 092arxiv:1510.04239




Phase Difference in B+ → K+µ+µ− Decays



How Large are the cc Contributions?

q2 Spectrum (B0 → K∗0µ+µ−)

]4c/2 [GeV2q0 5 10 15

5'P

-2

-1

0

1

2LHCb

SM from DHMV

µ+

µ−

uu

b s

W

u, c, t

Z/γ

B+ K+

I Short-distance effects: Electroweak penguinsI Long-distance effects from intermediate resonances: J/ψ, ψ(2S), higher cc states→ Associated with large uncertainties: usually avoided

I Contribution from J/ψ can potentially extent all the way to q2 = 0

GoalI Provide additional insights using the ground-state system B+ → K+µ+µ−

→ Allows precise Lattice calculations→ Can still use branching fraction to constrain Wilson coefficients



Study of B+ → K+µ+µ− LHCb-PAPER-2016-045, to appear in EPJC, arxiv:1612.06764

ObjectivesI Phase difference between J/ψ, ψ(2S) and the penguin contributionI Wilson coefficients C9 and C10

I B(B+ → K+µ+µ−)

Strategy

I Select B+ → K+µ+µ− candidates with mKµµ in 80 MeV/c2 window around B+

I Model mµµ over full range, including the resonance regions

→ J/ψ and ψ(2S) are modelled using a Breit-Wigner

→ Penguin is modelled using Wilson coefficients and form factors

]2c [MeV/µµKm5500 6000 6500

)2 cC

andi

date

s / (

5 M

eV/

210

310

410

510

LHCb

Signal

Specific backgrounds

Partially reconstructedbackground

Combinatorial background

Data


http://lhcbproject.web.cern.ch/lhcbproject/Publications/LHCbProjectPublic/LHCb-PAPER-2016-045.html

https://arxiv.org/abs/1612.06764


Main Results LHCb-PAPER-2016-045, to appear in EPJC, arxiv:1612.06764

I 4-fold degenerate solution: phases of J/ψ and ψ(2S) can be + or −

ϕJ/ψ < 0 and ϕψ(2S) < 0 Solution

] 2c [MeV/recµµm

1000 2000 3000 4000

)2 cC

andi

date

s / (

22 M

eV/

50−

0

50

100

150

200

250

300

datatotal

short-distance

resonances

interferencebackground

LHCb

Wilson Coefficients

)9CRe(0 2 4 6

)10

CR

e(

6−

4−

2−

0

SM

68.3

%

95.5%

99.7%

LHCb

Branching Ratio

I Short-distance component (full mµµ range, no extrapolation)

B(B+ → K+µ+µ−) = (4.37± 0.15 (stat)± 0.23 (syst))× 10−7





Search for B0s → µ+µ−µ+µ− and B0 → µ+µ−µ+µ−



Search for the Rare Decays B → µ+µ−µ+µ−

Resonant

s

W

c

c

s

b

µ−

µ+

µ−

µ+

φ

J/ψ

Non-Resonant

W

t

γ

Wγ,Z0

d, s

b

µ−

µ+

µ−

µ+

New Physics

S

P

s, d

b

µ−

µ+µ−

µ+

4 Muon Final State:

1 Intermediate J/ψ, ψ(2S) and φ resonances

→ Most abundant: B0s → J/ψφ with B(B0

s → J/ψφ) = (1.83± 0.18)× 10−8

2 Non-resonant component (Signal)

→ SM expectation: B(B0s → µ+µ−µ+µ−)

SM∼ 3.5× 10−11

Y. Dincer and L. Sehgal, PLB 556 (2003) 169, arxiv:hep-ph/0301056

3 New physics contributions→ For example, MSSM model with scalar (S) +pseudo-scalar (P) sgoldstino interactions→ Motivated by excess seen by HyperCP collaboration: Σ+ → P(→ µ+µ−)p

HyperCP, PRL 94 (2005) 021801, arxiv:hep-ex/0501014


https://dx.doi.org/10.1016/S0370-2693(03)00131-X

https://arxiv.org/abs/hep-ph/0301056

https://dx.doi.org/10.1103/PhysRevLett.94.021801

https://arxiv.org/abs/hep-ex/0501014


Analysis Strategy LHCb-PAPER-2016-043, to appear in JHEP, arxiv:1611.07704

Selection

1 Resonant components: Veto φ, J/ψ and ψ(2S) mass windows in all µ+µ− comb.

2 Combinatorial background: Selection is based on a MatrixNet [JMLR Proc. 14 (2011) 63]

3 Background from π → µ misidentification: Particle identification requirements

Event YieldI Split data into Far Sideband, Near Sideband and Signal regionsI PID and MatrixNet cuts optimised using Near Sideband regionI Background yield in Signal region extrapolated from fit to Far Sideband

4500 5000 5500 6000 m(µ+µ−µ+µ−)[MeV/c2]

0

1

2

3

4

5

6

Can

dida

tes /

(34

MeV

/c2)

LHCb dataB 0s search region

B 0 search region

signal regionnear sidebandfar sideband

Signal Region

I Expected Bkg yields

Nbkg(B0) = 0.55± 0.31

Nbkg(B0s ) = 0.47± 0.29





Main Results LHCb-PAPER-2016-043, to appear in JHEP, arxiv:1611.07704

I No events found in Signal region

I Set limit on braching ratio

B(B0s → µ+µ−µ+µ−) = αs×Nobs

µ+µ−µ+µ−

I with normalisation mode B+ → J/ψK+

αs ≡ εJ/ψK+

× B(B+ → J/ψK+)

ε4µ × NJ/ψK+× fu

fs

I Single event sensitivity:

αs = (2.29± 0.16)× 10−10

αd = (8.65± 0.80)× 10−10 ]9− 10×) [ − µ+ µ− µ+ µ→ 0

s(BΒ

0 2 4 6 ]9

− 10×

) [

− µ

+ µ− µ

+ µ→ 0

(BΒ

0

0.2

0.4

0.6

0.8

1

1.2

1.4

1.6

1.8

2LHCb

95% CL Exclusion

observed

σ 1 ±expected

σ 2 ±expected

Branching Fraction Limits (CLs Method)

B(B0 → µ+µ−µ+µ−) < 6.9× 10−10 @ 95 % C.L.B(B0

s → µ+µ−µ+µ−) < 2.5× 10−9 @ 95 % C.L.





B0s → µ+µ− Branching Ratio and Effective Lifetime



Search for the Rare Decays B → µ+µ−

I Theoretically clean quantity → accurate SM prediction

B(B0 → µ+µ−)SM= (1.06± 0.09)× 10−10

B(B0s → µ+µ−)

SM= (3.66± 0.23)× 10−9

Bobeth et al., PRL 96 (2006) 241802, arxiv:hep-ex/0511015

Current Status

ATLAS, EPJC 76 (2016) 513, arxiv:1604.04263

CMS+LHCb, Nature 522 (2015) 68, arxiv:1411.4413Kristof De Bruyn (CPPM) b → s`+`− and Rare Decays at LHCb La Thuile 2017 14 / 31

http://arxiv.org/abs/hep-ex/0511015




Analysis Strategy LHCb-PAPER-2017-001

In a Nutshell

I Same strategy as for the Run 1 CMS+LHCb analysisI Selection based on: BDT + particle identification (PID)

→ BDT output is flat for signal, calibrated on B0 → K+π−

→ BDT output peaks towards zero for background, calibrated on mass sidebands

I Fit the mµ+µ− mass in bins of BDT output

Improvements

I Larger data sample: 3 fb−1 Run 1 + 1.4 fb−1 of Run 2

I New and improved signal isolation

I New and improved BDT: 50% better background rejection

I Improved PID requirements: 50% less B → h+h− background

Normalisation

I Two control channels: B+ → J/ψK+ and B0 → K+π−

I Dependence of hadronisation fraction fs/fd on√s evaluated comparing

B+ → J/ψK+ and B0s → J/ψφ



Analysis Strategy LHCb-PAPER-2017-001

Mass Fit

I Unbinned maximum likelihood fit in 4 bins of BDT output

I mµ+µ− ∈ [4900, 6000] MeV/c2

I Exclude BDT< 0.25 (background dominated)

I Simultaneous fit of Run 1 and Run 2 data

I Free parameters: B(B0s → µ+µ−), B(B0 → µ+µ−) and comb. bkg.

I Exclusive background yields are constrained in fit

Exclusive Backgrounds

I Decays with two real muonsI B+

c → J/ψµ+νµ

I B0(+) → π0(+)µ+µ−

I Decays with hadrons misidentified as muonsI B → h+h− (peaking in signal region)I B0 → π−µ+νµI B0

s → K−µ+νµI Λ0

b → pµ+νµ



A Nice Peak! LHCb-PAPER-2017-001

]2c [MeV/−µ+µm5000 5500 6000

)2C

andi

date

s / (

50

MeV

/c

0

5

10

15

20

25

30

35 Total−µ +µ →s

0B−µ +µ →0B

Combinatorial−

h'+ h→B

µν +µ) −

(K−π →(s)0B

−µ +µ 0(+)π →0(+)B

µν −µ p →b0Λ

µν +µ ψ J/→+cB

LHCb

BDT > 0.5

Branching Fractions

B(B0s → µ+µ−) = (3.0± 0.6 (stat) +0.3

−0.2 (syst))× 10−9 (7.8σ)

B(B0 → µ+µ−) = (1.5 +1.2−1.0 (stat) +0.2

−0.1 (syst)) × 10−10 (1.6σ)

Branching Fraction Limit (CLs Method)

B(B0 → µ+µ−) < 3.4× 10−10 @ 95 % C.L.



2D Contours LHCb-PAPER-2017-001

)−µ+µ → 0s

BF(B0 2 4 6 8

9−10×

)− µ+ µ

→ 0B

F(B

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.99−10×

68.27%

95.45%

99.73%

99.99%

SM

LHCb



B0s → µ+µ− Effective Lifetime

I Even if B(B0s → µ+µ−) = B(B0

s → µ+µ−)SM, NP can still hide in this decay

I Need a second, complementary observable to find it:

either CP asymmetry parameter Aµ+µ−

∆Γ or effective lifetime τµ+µ−

I Defined as

τµ+µ− ≡∫∞

0t〈Γ(Bs(t)→ µ+µ−)〉dt∫∞

0〈Γ(Bs(t)→ µ+µ−)〉dt

I They are related

τµ+µ− =τBs

1− y 2s

[1 + 2Aµ

+µ−

∆Γ ys + y 2s

1 +Aµ+µ−

∆Γ ys

]I where

ys ≡ τBs ∆Γs/2 = 0.062± 0.006

0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0 2.2 2.4R ≡ BRexp(Bs→ µ+µ−)/BRSM(Bs→ µ+µ−)

−1.0

−0.8

−0.6

−0.4

−0.2

0.0

0.2

0.4

0.6

0.8

1.0

A∆

Γ(B

s→

µ+µ−

)

|P | = 1, |S| = 0, ϕP = 0

SM

ϕP = π/4

ϕP = π/2

|P | = 1, |S| = 0

|S| = |P |

ϕS = π/2

ϕS = π/4

ϕS = 0

Scalar NP (C(′)S )

Non-scalar

NP (C(′)10,C

(′)P )

|S|, ϕS free; |P | = 1; ϕP = 0

ϕP free; |S| = 0; |P | = 1± 10%

Excluded at 95% C.L.

K. De Bruyn et al., PRL 109 (2012) 041801

arxiv:1204.1737




B0s → µ+µ− Effective Lifetime LHCb-PAPER-2017-001

Analysis Strategy

I Apply same selection, but looser cuts

I Reduces mass windowmµ+µ− ∈ [5320, 6000] MeV/c2

I Step 1: Mass fit to derive weights(sPlot technique)

I Step 2: Fit to weighted decay timedistribution

I Strategy validated on B0 → K+π−

τB0 = 1.52± 0.03 (stat) ps

I Compare to

τPDGB0 = 1.520± 0.004 ps

]2c [MeV/−π+Km5200 5300 5400 5500

)2 cC

andi

date

s / (

10

MeV

/

0

100

200

300

400

500

Total−π+ K→s

0B

−π+ K→0BCombinatorial

LHCb

decay time [ps]0 5 10

Can

dida

tes

/ (1

ps)

0

100

200

300

400

500

600LHCb



B0s → µ+µ− Effective Lifetime LHCb-PAPER-2017-001

]2c [MeV/−µ+µm5400 5600 5800 6000

)2 c c

andi

date

s / (

34 M

eV/

− µ+ µ

→ s0 B

0

2

4

6

8

10

12

14

16

18

DataTotal

−µ+µ → s0B

Combinatorial background

LHCb

Decay time [ps]0 5 10

can

dida

tes

/ (1

ps)

− µ+ µ

→ s0W

eigh

ted

B

0

2

4

6

8

Data

Effective lifetime fit

LHCb

Results

τ(B0s → µ+µ−) = 2.04± 0.44 (stat)± 0.05 (syst) ps

I Consistent with both Aµ+µ−

∆Γ = 1 (1σ) and Aµ+µ−

∆Γ = −1 (1.4σ)

I Does not yet constrain any NP models



Search for B0s → τ+τ− and B0→ τ+τ−



Search for the Rare Decays B → τ+τ−

I In the SM, only difference between B0s → τ+τ− and B0

s → µ+µ− is due to helicitysuppression (lepton mass)

I Theoretically clean quantity → accurate SM prediction

B(B0→ τ+τ−)SM= (2.22± 0.19)× 10−8

B(B0s → τ+τ−)

SM= (7.73± 0.49)× 10−7

Bobeth et al., PRL 96 (2006) 241802, arxiv:hep-ex/0511015

I Current best limit:B(B0→ τ+τ−) < 4.1× 10−3 @ 90% C.L.

BaBar, PLB 687 (2010) 139, arxiv:1001.3221

LHCb Analysis for B0s → τ+τ−

I Reconstructed in hadronic τ− → π−π+π−ντ mode (both τs)→ Low efficiency: B(τ− → π−π+π−ντ ) = (9.31± 0.05)%

I Normalisation mode: B0 → D+(→ π+K−π+)D−s (→ K−K+π−)


http://arxiv.org/abs/hep-ex/0511015



Experimental Signature

B0s → τ+τ−

PV

τ+

π+

π−

π+

ντ

τ− π−

π+

π−ντ

B0s

B0 → D+D−s

PV

D+

π+

K−

π+

D−s

K−

K+

π−

B0d

Challenges

1 2 missing neutrinosI No narrow (mass) peak to fitI Cannot differentiate B0

s from B0

2 6 pions = large combinatorial backgroundI Use isolation variables to suppress backgroundI Use decay geometry to approximately reconstruct the B and τ properties



Intermediate Resonances

I Predominantly proceeds through

τ− → a−1 (1260)ντ → ρ0(770)π−ντ .

I Exploit this in analysis

Dec

ays

0

5

10

15

20

25

]2c[MeV/ −π+πm200 400 600 800 1000 1200

]2 c[M

eV/

− π+ πm

200

400

600

800

1000

1200

1 2 3

4 5 6

7 8 9

LHCb simulationSubsamples:

I Signal Region [SR]:(τ+ ∈ 5) & (τ− ∈ 5)

I Signal-Depleted Region:(τ+ ∈ 1, 3, 7, 9) ||(τ− ∈ 1, 3, 7, 9)

I Control Region [CR]:(τ± ∈ 4, 5, 8) & (τ∓ ∈ 4, 8)

Selection:

I Cut-based loose selection

I Two-stage neural network



Fit Strategy LHCb-PAPER-2017-003, arxiv:1703.02508

I Perform a 1-dimensional histogram fit to the output of a neural network

I Output is remapped such that signal is flat

I The Signal templates are taken from simulation

I The Background template is taken from data control region

Neural network output0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1

Frac

tion

of d

ecay

s

0

0.02

0.04

0.06

0.08

0.1

0.12

0.14

0.16

−τ+τ→0sB

LHCb simulation

Signal regionControl region


Frac

tion

of c

andi

date

s

3−10

2−10

1−10

1

Control regionLHCb





Fit Model LHCb-PAPER-2017-003, arxiv:1703.02508

Events:

Signal: 16% B0s → τ+τ− Simulation versus 7% data

Sig.-Depleted: 13% B0s → τ+τ− Simulation versus 37% data

Control: 58% B0s → τ+τ− Simulation versus 47% data

I . . . so the data control region might also contain signal.

Model:

N SRdata = s × N SR

sim + fb ×(N CR

data − s · εCR

εSR× N CR

sim

)I s: signal yield (free parameter)

I fb: scaling factor for background template (free parameter)

I εi : efficiencies, taken from simulation

I : indicates normalised distributions





Fit to Data LHCb-PAPER-2017-003, arxiv:1703.02508

Background-Only Model

Can

dida

tes

1

10

210

310

410

LHCb

DataTotalBackground


Pull

5−0

5

Nominal Fit Model

Can

dida

tes

1

10

210

310

410

LHCb

DataTotal

Signal×1 −Background


Pull

5−0

5

Nobsτ+τ− = s = −23± 71

I Compatible with the background-only hypothesis

→ Set an upper limit





From Yield to Branching Ratio LHCb-PAPER-2017-003, arxiv:1703.02508

B(B0s → τ+τ−) = αs × Nobs

τ+τ− ,

I Assume all signal comes from B0s → τ+τ−, i.e. ignore B0→ τ+τ− completely

I Determine αs using B0→ D−D+s normalisation mode

αs =εD−D+

s × B(B0→ D−D+s )× B(D+ → π+K−π+)× B(D+

s → K+K−π+)

NobsD−D+

s× ετ+τ− × [B(τ− → π−π+π−ντ )]2 × fd

fs

I Fit to data, Efficiencies from simulation, External Input

αs = (4.07± 0.70)× 10−5 → NSMτ+τ− = 0.019

αd = (1.16± 0.19)× 10−5 → NSMτ+τ− = 0.002





Branching Fraction Limit LHCb-PAPER-2017-003, arxiv:1703.02508

B0s → τ+τ−

)−τ+τ→0sB(B

0 0.002 0.004 0.006 0.008 0.01

-val

uep

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

LHCb

B0→ τ+τ−

)−τ+τ→0B(B0 0.0005 0.001 0.0015 0.002 0.0025 0.003

-val

uep

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

0.9

1

LHCb

Branching Fraction Limit (CLs Method)

B(B0s → τ+τ−) < 6.8× 10−3 @ 95 % C.L.

B(B0→ τ+τ−) < 2.1× 10−3 @ 95 % C.L.





Conclusion

I Study of the short and long-distance effects in B+ → K+µ+µ−

B(B+ → K+µ+µ−) = (4.37± 0.15 (stat)± 23 (syst))× 10−7

I Improved limits on the B → µ+µ−µ+µ− branching ratios

B(B0 → µ+µ−µ+µ−) < 6.9× 10−10 @ 95 % C.L.

B(B0s → µ+µ−µ+µ−) < 2.5× 10−9 @ 95 % C.L.

I Improved measurement of B0s → µ+µ− branching ratio New!

B(B0s → µ+µ−) = (3.0± 0.6 (stat) +0.3

−0.2 (syst))× 10−9

B(B0 → µ+µ−) < 3.4× 10−10 @ 95 % C.L.

I First measurement of the B0s → µ+µ− effective lifetime New!

τ(B0s → µ+µ−) = 2.04± 0.44 (stat)± 0.05 (syst) ps

I First limit on the B0s → τ+τ− branching ratio New!

B(B0s → τ+τ−) < 6.8× 10−3 @ 95 % C.L.

B(B0→ τ+τ−) < 2.1× 10−3 @ 95 % C.L.Kristof De Bruyn (CPPM) b → s`+`− and Rare Decays at LHCb La Thuile 2017 31 / 31


Supplementary Material



The LHCb Detector JINST 3 (2008) S08005

Forward arm spectrometer to study b- and c-hadron decaysI Pseudo-rapidity coverage: 2 < η < 5

I Good impact parameterresolution to identifysecondary vertices:(15 + 29/pT) µm

I Invariant mass resolution:8 MeV/c2 (B → J/ψX )22 MeV/c2 (B → hh)

I Excellent particleidentification:95 % K ID efficiency(5 % π → K mis-ID)

I Versatile & efficienttrigger for b- andc-hadrons and forwardEW signals


https://dx.doi.org/10.1088/1748-0221/3/08/S08005


B+ → K+µ+µ− LHCb-PAPER-2016-045, to appear in EPJC, arxiv:1612.06764

I 4-fold degenerate solution: phases of J/ψ and ψ(2S) can be + or −

] 2c [MeV/recµµm

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)2 cC

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B+ → K+µ+µ− LHCb-PAPER-2016-045, to appear in EPJC, arxiv:1612.06764

J/ψ negative/ψ(2S) negative J/ψ negative/ψ(2S) positiveResonance Phase [rad] Branching fraction Phase [rad] Branching fraction

ρ(770) −0.35± 0.54 (1.71± 0.25)× 10−10 −0.30± 0.54 (1.71± 0.25)× 10−10

ω(782) 0.26± 0.39 (4.93± 0.59)× 10−10 0.30± 0.38 (4.93± 0.58)× 10−10

φ(1020) 0.47± 0.39 (2.53± 0.26)× 10−9 0.51± 0.37 (2.53± 0.26)× 10−9

J/ψ −1.66± 0.05 – −1.50± 0.05 –ψ(2S) −1.93± 0.10 (4.64± 0.20)× 10−6 2.08± 0.11 (4.69± 0.20)× 10−6

ψ(3770) −2.13± 0.42 (1.38± 0.54)× 10−9 −2.89± 0.19 (1.67± 0.61)× 10−9

ψ(4040) −2.52± 0.66 (4.17± 2.72)× 10−10 −2.69± 0.52 (4.25± 2.83)× 10−10

ψ(4160) −1.90± 0.64 (2.61± 0.84)× 10−9 −2.13± 0.33 (2.67± 0.85)× 10−9

ψ(4415) −2.52± 0.36 (6.04± 3.93)× 10−10 −2.43± 0.43 (7.10± 4.48)× 10−10

J/ψ positive/ψ(2S) negative J/ψ positive/ψ(2S) positiveResonance Phase [rad] Branching fraction Phase [rad] Branching fraction

ρ(770) −0.26± 0.54 (1.71± 0.25)× 10−10 −0.22± 0.54 (1.71± 0.25)× 10−10

ω(782) 0.35± 0.39 (4.93± 0.58)× 10−10 0.38± 0.38 (4.93± 0.58)× 10−10

φ(1020) 0.58± 0.38 (2.53± 0.26)× 10−9 0.62± 0.37 (2.52± 0.26)× 10−9

J/ψ 1.47± 0.05 – 1.63± 0.05 –ψ(2S) −2.21± 0.11 (4.63± 0.20)× 10−6 1.80± 0.10 (4.68± 0.20)× 10−6

ψ(3770) −2.40± 0.39 (1.39± 0.54)× 10−9 −2.95± 0.14 (1.68± 0.61)× 10−9

ψ(4040) −2.64± 0.50 (4.05± 2.76)× 10−10 −2.75± 0.48 (4.30± 2.86)× 10−10

ψ(4160) −2.11± 0.38 (2.62± 0.82)× 10−9 −2.28± 0.24 (2.68± 0.81)× 10−9

ψ(4415) −2.42± 0.46 (6.13± 3.98)× 10−10 −2.31± 0.48 (7.12± 4.94)× 10−10





B → µ+µ−µ+µ− LHCb-PAPER-2016-043, to appear in JHEP, arxiv:1611.07704

HyperCP-inspired MSSM Scenario

I Single event sensitivity:

αs(MSSM) = (2.01± 0.14)× 10−10

αd(MSSM) = (7.75± 0.72)× 10−10

]9− 10×) [ − µ+ µ→(PΒ ×) − µ+ µ →(SΒ × S P) → 0s

(BΒ0 2 4 6

]9−

10×)

[

− µ+ µ

→(P

Β ×)

− µ+ µ

→(S

Β × S

P)

→ 0(B

Β

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1.8

2LHCb

S P→ 0s S P; B→ 0B

− µ+ µ →; P − µ+ µ →S

= 214 MeVP

= 2.5 GeV; mSm

95% CL Exclusion

observed

σ 1 ±expected

σ 2 ±expected

Branching Fraction Limits (CLs Method)

B(B0 → S(→ µ+µ−)P(→ µ+µ−)) < 6.9× 10−10 @ 95 % C.L.

B(B0s → S(→ µ+µ−)P(→ µ+µ−)) < 2.5× 10−9 @ 95 % C.L.




New Physics Searches with bs+- Transitions and Rare Decays ... · B+ !K+ + B ! + + B ! + B !˝+˝...

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Transcript of New Physics Searches with bs+- Transitions and Rare Decays ... · B+ !K+ + B ! + + B ! + B !˝+˝...