The CKM Picture

●CKM triangle has been (over)constrained in experiments such as BaBar, Belle,CLEO the Tevatron and others ●Very successful description of CP violation

New Physics in B mixing?

B_d mixing SM like, expected since tree decay

B_s mixing less constrained (small in SM)

The angle βs with Bs → J/ψφ

Golden Decay Channel for LHC• Bs → J/ψφ is strange counterpart of Bd → J/ψK0

• Cannot be done at Belle/BaBar

Complicated analysis• final state has two vector mesons, a mixture of CP-even (S

and D waves) and CP-odd (P wave) eigenstates, need angular analysis

SM prediction small:

s=−2s=−22=−2.05°

The angle βs with Bs → J/ψφ

CDF: [PRL 100 (2008) 161802]

First βs tagged analyses from Tevatron

D0: arXiv:0802.2255

Global analysis based on Tevatron results

βs reach with 2009 data

Would contradict MFV hypothesis

Another interesting channel, has no tree level contribution

GIM suppression leads to

→ theoretically clean& one-loop effect → good NP observable

In SM:

And

BaBar and Belle get a negative value:

2.7 sigma deviation,

A ss s=P c−P tV cbV cs∗Pu−P sV us∗V ub

1−As ss/ As ssO 2

ℑB−K s=sin2

B−J /K s−B−K sO 2

sin 2K s=−0.39±0.41

b→sss

B_s→ΦΦ

LHC won't be able to improve in this channel by much, golden decay channel B_s->ФФ

In SM:

After 10/fb: σ( ΔФ)=.05

ℑB−0.01

24.09.08 V.Gibson SUSSP57 St Andrews 10

FCNC decays b→d(s) only occur in loop diagrams in the Standard Model

• Exclusive Br’s expected ~O(10-5) or smaller in SM

B→K*γ , B →K*+-, B →µ +µ −

Excellent probe of new physics

• Within the Standard Model, rare decays are sensitive to the CKM matrix elements Vts and Vtd

Complementary measurements

Rare B Decays

b

sd ,

tcu ,,W-

γ,0Z

b

sd ,

tcu ,,

W

γ,0Z

b

sd ,

γ,0Z

New particle

loops

24.09.08 V.Gibson SUSSP57 St Andrews 11

B→µ µ

CMS expect 7 signal events with <1 background 5σ observation with 30fb-1

SM expectation• Br(Bs→µ µ ) = (3.5± 1.0)x10-9

• Br(Bd→µ µ ) = (1.0± 0.5)x10-10

Mass resolution Mass resolution

Full Full TrackerTracker

σ = 46 MeV

Bs→µ µ

Number events expected Bs→µ µ Bd →µ µ Bkgd

92 14 660 1 yr (1034cm-2s-1)

26 4.1 <6.4

24.09.08 V.Gibson SUSSP57 St Andrews 12

B→µ µ

Easy to trigger and reconstruct at LHC

Strong enhancement in CMSSM:

B K*µ µ

In SM this bs penguin decay contains right-handed calculable contribution but this could be added to by NP resultingin modified angular distributions

SM

B → K* μμ

?A very important property isforward-backward asymmetry..

..and position of its zero, which is robust in SM:

)(

2

09

70 sC

Cs

eff

eff

−=

AFB(s), fast MC, 2 fb–1  

 s = (mµ µ )2 [GeV2]

B K*µ µ : LHCb prospects

Forward-backward asymmetry AFB (s) in µ µ - rest frame is a sensitive NP probe Predicted zero of AFB (s) depends on Wilson coefficients C7

eff / C9eff

AFB(s), fast MC, 2 fb–1  

 s = (mµ µ )2 [GeV2]

7.2 k events / 2fb-1 with B/S ~ 0.4 After 10 fb-1zero of AFB located to ±0.28 GeV2 providing 7% stat. error on C7

eff / C9eff

Full angular analysis gives better discrimination between models. Looks promising

Summary

In B-Physics one can probe New Physics via off-shell corrections

Promising hints for new physics from Tevatron and B-Factories

Most promising channel for 2009: βs