1. LHCb Physics Program On behalf of LHCb collaboration M.N Minard (LAPP)
Status LHCb ( R.Jacobson)
Single arm spectrometer
B- physics dedicated
M.N Minard
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2. Improve precision on CKM parameters
Impressive results from B factories & K sector
Good agreement with SM
Indirect
Direct measurement
b->s transitions emerging
Tevatron results
Belle
LHCb domain
Strong constraints from SM on KM sector
Direct g measurement :LHCb
M.N Minard
Aspen Winter Meeting 2009

3. LHCb hints for NP
Hints for NP contribution in loop processes as tree and box / penguin diagrams.
NP from CPV domain precision measurements :
Observe deviations from SM expectations
Confront measurements between channels expecting different NP interference
Fs , mixing phase of the Bs system
g measurements
NP from rare decays high precision measurements :
Branching ratio
Time asymmetry measurements
EW penguin
Radiative penguin
Strong penguin
Oscillation box
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4. LHCb apparatus caracteristics
High statistics on all b and c species :
2fb-1: 1012 bb pairs
Heavy flavor precision experiment
Lepton and hadron trigger
Efficient particle ID
Decay time resolution
Flavour tagging
btag Bs K K
p+, K  Ds
Primary vertex
proper time resolution ~ 40 fs
BsDs(KKπ)K
B0-> J/y K0s
Sensitivity: 236k events/2 fb-1
s(sin2b) = 0.020
[B factories: (850 fb1)]
Bs→ Ds K
Bs →Ds p
ε(KK) : 97%
ε(πK) : 5%
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5. Bs mixing phase s
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6. Bs phase Fs +NP? b c b t W B0s B0s s s W
Lifetime B0s, B0s distributions give oscillation pattern of frequency ms and amplitude ~ sins trough the phase in the mixing box diagram. s =-2bs
Φs can be extracted from CP time-dependent asymmetry decay rates :
with nf = ±1 CP eigenstate
Bs  J/Ψ η, Bs  J/Ψ η’, Bs  ηc Φ Bd  Ds+ Ds- CP eigenstate
Bs -> J/Ψ f , mixing +-1 CP eigenstate
NP may modify the mixing phase
M.N Minard
Aspen Winter Meeting 2009

7. Bs phase Fs (2) Current results from Tevatron:
D bs= with 2.8 fb-1
CDF bs = 68%CL with 2.8 fb-1
Use of pure CP eigenstates statistic limited
Bs -> J/Ψ  large yield, low background
mixture of CP = +1 and CP = -1 states
angular analysis to disentangle the two states
SM FS(Bs -> J/Ψ ) = -2bs = ±
s(ΔGs/Gs) = 0.0092
With 10 fb-1 stat(Fs) 0.009
> 3 for non-zero Fs of SM
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8. Room for NP in Bs mixing
The effects of New Physics in the oscillation can be parameterized as:
arXiv:
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9. bsss hadronic penguin decays
In SM CP violation < 1% due to cancellation of the
mixing and penguin phase:
Bs  SM  2 arg(Vts*Vtb) – arg(VtsVtb*) = 0
In presence of NP expect different
contributions in boxes and in penguins:
Bs  NP = MixingNP - DecayNP
+ NP?
Vtb
Vts
Mixing
box
+ NP?
Mixing CP asymmetry angular analysis & time dependance of flavour tagged events
For 2 fb–1 stat(SM) = 0.11
Bd related quark penguin
Bd  f KS & Bd  J/yKS
expected precision: (sin(2eff)) ≈0.23
Channel
Yield (2 fb-1)
B/S (90%CL)
Bs  f f
3100
< 0.8
Bd  f KS
920
< 1.1
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10. g related measurements
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Aspen Winter Meeting 2009

11. Fs+  from Bs  DsK
2 Trees : b->c & b->u interfere through Bs mixing
Measure Fs+g . Ratio extracted from data
Channel
Yield (2 fb-1)
B/S (90%CL)
Bs  DsK
6200
< 0.2
Bs  Ds 
140 k
0.4
p-K id
Bs→ Ds-p+
Bs→ Ds-K+
Include Bs Dsp to constrain Dms
Fit time-dependent rates of Bs→DsK and Bs→Dsp
Fs + 
9-12
ms
0.007 ps-1
Sensitivity with 2fb–1:
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12. g from trees: BDK fD(CP)K– D0K– B– fD(K+p-)K– fD(K-p+)K– _ bc bu
Two tree amplitudes (bc & bu) interfere in
decays to a common D0 and D0 state fD
Exploit interference according the
decay mode ( analysis from B-factories).
GLW : CP eigenstate of D (*)0
D0-> K+K-/p+p- , Ksp0
ADS : Use common flavor state
- doubly cabbibo supressed D0-> K+p-
Lower event rate / large asymmetry
- Favoured mode: Large event rate / tiny asymmetry
Dalitz for 3 body decays _
For each mode
parameters g,(rb,db)
fD(K+p-)K–
D0K–
bc
bu B–
fD(CP)K–
fD(K-p+)K–
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13. g from loops: B0d/sh+h-
Interference of bu tree & bd(s) penguin diagrams leads to CP violation depending on g (Sensitive to NP)
Adir & Amix depend on mixing phase 2b,g, and ratio of penguin to tree amplitudes = d eiq
B0 p+p- and Bs0  K+K- (d->s) diagrams
U-spin symmetry.
4observables: (Adir & Amix )pp, (Adir & Amix )kk
Parameters : g, penguin to tree amplitudes (d eiq) pp, , kk NP
decay
Yield (2fb-1)
B/S
B0 p+p-
36k
0.5
Bs0  K+K-
1.5
s(g)
In 2fb-1
10°
Compare to g from trees to get hints of NP in penguins
M.N Minard
Aspen Winter Meeting 2009 13

14. g from trees: BDK tree HLT trigger K-p PID Mass resolution
B mode
D mode
Method
Yield
(2fb-1)
sensitivity
Parameter
Bs→DsK
KKp
tagged, ACP(t)
6.2K
g+2bs
B+→D K+
favo Kp
ADS
56K
8.2
9.6 °
Strong phases g
suppr *
KK/pp
counting, GLW
8.6k
B± D0 K±
K3p
61K
B± D0*K±
D0p0/D0g
GLW +ADS
42K
K+K-p+p
GLW Dalitz
1.7
18°
B0 D0K*0
Kp,KK,pp
ADS+GLW 5K
6-25
B→pp,KK -
tagged, ACP(t)
36K 10
g /bd / bs
HLT trigger
K-p PID
Mass resolution
tree
Global fit from
ADS/GLW under
dB°assumption =35° Rb
Combine tree – 2fb-1
s(g) : 4°
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15. Rare decays
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16. Rare decays seeking for NPZ, m+ m- g g
NP? in
BR(SM)
BR exp
@ LHCb
Large
Theory
Error
On br
Bsfg
g polarization
( ) Belle’08
dC7
B0K*m+m-
( )·10-6 B factories
angular distributions
dC7, dC9 « 
Bsm+m-
(3.35±0.32)·10-9
helicity suppressed
TeVatron @ 90% CL (2 fb-1) < 4510-9 BR
S-P
coupling
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17. Bs  mm Ex: NUHM1 Helicity suppressed – NP sensitivity
in SM: BR(Bs→mm) (3.35 ± 0.32) x 10-9
Enhancement from SUSY model :
BR(Bs→ mm)  tan6b/MH2
Sensitive to new physics coupling with
Scalar & pseudo scalar
Ex :
Possible enhancement
BR(Bs+-)~20x10-9
J.Ellis et al. arXiv: v1 [hep-ph] (2007)
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18. Bs  mm Analysis relies on : (arbitrary normalization)
Geometry Likelihood (GL) :
geometrical properties ( muon IPS,
B lifetime, isolation, IP)
Good mass resolution
Particle ID : DLL (-) & DLL(-K)
- Sensitive Region: GL > 0.5
- Statistical method applied to separate signal from background
SM BR, in 2fb-1 21 signal events
172 background events
(arbitrary
normalization)
(arbitrary
normalization)
Major uncertainty on BR from relative Bs,B+ hadronization fractions 14%.
Bs branching ratio determination useful
M.N Minard
Aspen Winter Meeting 2009

19. Bs  mm 90% exclusion Main uncertainty hadronization fraction
Expected CDF+D0 limit 8fb-1
90% exclusion
Main uncertainty hadronization fraction
Within SM BR:
2 fb–1  3 evidence
10 fb–1  5 observation
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20. B0K0*m+m- NP NP can affect:
, Z0
Suppressed Loop FCNC process (EW penguins)
Several observables to test the dynamics
Afb (s=mll2)
Angular distributions: ql, f, qK*
Invariant mass m+m- s =(mmm)2 =q2
NP can affect:
Forward-backward asymmetry AFB(s) in ql distribution
Dependence on s (predicted by several models)
Zero of AFB(s)
SM s0= GeV2/c4 NP
Example 2 fb-1
experiment
10 fb (s0)=0.28)
Afb
Mmm2 (GeV2)
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21. g polarization in Bs  fg
Bsfg FCNC radiative penguin
Time dependent CP asymmetry
probe SM/NP
Adir  0, Amix  sin2y sin2f ,
AD  cos 2y cosf
tan y = |b→s g R| / | b→s g L|~ cos f  1
In SM : C =0 , S= sin2y sinf , Ad = sin2y cosf
Sensitivity ; s(C) , s(S ) = fb-1
SM extensions (left-right-symmetric, unconstrained MSSM) predict large tan y while no change on inclusive BR (bsg)
M.N Minard
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22. Conclusions LHCb is looking forward for the 1st collisions
Interesting results can comme early ( 0.5 fb-1)
Bs→ J/j f Fs measurement with 0.05 precision
Bs -> mm BR limit close SM value
Direct g measurement s(g) 10°
LHCb able to provide strong improvement in Bs sector
Potential and channels variety allows field for indirect NP discovery
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23. Backup
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24. Physics from (very) first data
Exploit minimum bias data (almost no trigger)
108 minimum 2kHz S=
σmb
σ∙ε
∙Nmb
Number of selected signal events:
M.N Minard
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25. Also studying Lepton Flavour Violation in 
Sensitivities for 100 fb-1
Also studying Lepton Flavour Violation in 
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26. Upgrade Increase L0 hadron bandwidth Manage a factor 110 in luminosity
Go from 1Mhz to 40 Mhz data flow
Implications :
Electronics and detector upgrade is being investigated
Change Vertex Locator to pixels 3D device
M.N Minard
Aspen Winter Meeting 2009

27. Rare decays B0  K*(K+p-)m+m- Bs  f(K+K-)g Bs m+m-
In the SM, b  s only through loops (FCNC) implies:
Processes are rare
Powerful to find/constraint NP!
Operator Product Expansion parametrize new physics effects through # b  s observables :
Observables are functions ofC’s.
Branching ratios (BR) Cs
Polarizations (C9)
Angular distributions (C7/C9)
Three examples for LHCb:
B0  K*(K+p-)m+m-
Bs  f(K+K-)g
Bs m+m-
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28. Full 3D Angular Analysis
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29. M.N Minard
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30. Charm Physics Sensitivity to NP : loop diagrams involves d quarks
Mixing
Mixing observed in Babar & Belle
x = 0.89± %
y = 0.75± %
. Time-dependent D0 mixing with wrong-sign D0K+– decays
. Direct CP violation in D0K+K–
M.N Minard
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31. With luminosity increase level of interest emerge: 0.5 fb-1
Bs→ J/j f : 0.05 precision on bs
Bs -> mm : improved limit
2 fb -1 (1year)
CPV
g from tree : 5
g from penguins 10
Bs mixing phase :
bs eff from penguins : 0.11
Rare decays
s0 0.5 GeV2 from BK*mm
Bs -> mm at 5 s
10fb-1
CPV
g from tree & loop : 4
g from penguins : 6
Bs mixing phase :
MS level
Rare decays
s0 0.3 GeV2 from BK*mm
Bs -> mm SM at 5 s
Bs-> fg s(Ad) =0.09
M.N Minard
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32. Room for NP in Bs mixing s hs hs ASLs LHCb expects
Ligeti, Paucci,Perez, hep-ph/
New Physics in Bs mixing amplitude M12 parameterized with hs and s: s
2006 including
ms measurement
Additional constraints can come from semileptonic Asymmetry. In SM: ASLs 10-5:. BsDsn
ASLs
With 2bs from
Bs J/
LHCb 2fb-1 hs
LHCb expects
109 events/ 2fb-1 d(ASLs )stat2x10-3 in 2fb-1 hs
M.N Minard
Aspen Winter Meeting 2009