CP violation and CKM (Theory)

July 31,2006 Yasuhiro Okada, ICHEP 06 1

CP violation and CKM (Theory)

Yasuhiro Okada (KEK)

July 31, 2006

ICHEP 06, Moscow

Yasuhiro Okada, ICHEP 06 2July 31,2006

CP violation and quark flavor mixing

CP violation was discovered in KL decays in 1964, much before the Standard Model was proposed. This was a big mystery.

Since then, there have been a great deal of progress in the elementary particle physics, which leads us to gauge interactions and three generations of quarks and leptons. Then, Kobayashi-Maskawa mechanism, proposed in 1972, has become a prime candidate for the theory of the CP violation.


In 2001, a large CP violation in the B sector was found at two B factories at KEK and SLAC. New discoveries in B decays have followed, such as a direct CP violation, b -> sll, and b->d

LHC will start running next year to explore TeV scale physics. Focus of flavor physics is also shifting to search for New Physics effects.

There are a variety of ways to explore New Physics in K, Bd/Bu, Bs, D physics. Important information has been already obtained.


Plan of this talk Unitarity triangle and New Physics B rare decays and B-> Bs mixing and Bs -> Future of flavor physics

New experimental results will be covered by other plenary speakers.


Cabibbo-Kobayashi-Maskawa matrix

The CKM matrix is a sole origin of flavor mixingand CP violation in the quark flavor transitionprocesses in the Standard Model.

Four parameters: A


Vus and CKM unitarity in the first row

Significant improvements inKaon semi-leptonic decays has been made at BNL, KTeV,CERN-NA48,KLOE, and ISTRA+ in recent years. (talks in session 8)

The CKM unitarity is now satisfied with ~1.

A proposal of Vus from decay (J.Prades)Vud from neutron life-time and A-asymmetry (A.Serebrov).

Nucleardecay B decay K decay

M.Antonelli


Unitarity triangle

mBd, mBs/mBd,

b->u transition

B(B->)/B(B->K*)

B(K0->0)B(K+ -> +)

K

CP asymmetries in bccs modes.CP asymmetries in BCP asymmetriesin BDK, etc.()/(2): CP asymmetry in BD, etc

Angle determination

Various observable quantities in K and B physics constrain the anglesand lengths of the unitarity triangle.


The unitarity triangle: a year ago

Already many observablequantities are over-constrainingthe unitarity triangle.


Is this enough?Not, to study New Physics effects.In order to disentangle new physicseffects, we should first determine CKMparameters by “tree-level” processes.

Fit from tree level processes

We know (or constrain) which sector is affected by new physics.Improvement of is essential.

|Vub|,

Bd mixing and CP asymmetries

eK and B(K)

Bs mixing and CP asymmetries

+

+

+

Pre-ICHEP 06


CP asymmetry in penguin-dominated processesSummer 2005

“sin “ is the same in the SM Summer 2006 update => M.Hazumi’s talk

Time-dependent CP asymmetry

(Dominant decay diagrams)B->J/Ks

“tree”

B->Ks

New phase (ex SUSY)“penguin”


Recent theoretical calculations on S= sin(21eff)-sin(21) There are efforts to calculate difference of CP asymmetries b

etween penguin-dominated modes and tree-dominated mode in different methods (QCD factorization, Final-state interaction, Soft Collinear Effective Theory).

Differences are estimated so far within a few % for B toKs and ’Ks modes in the Standard Model.

S(0Ks)

S(’Ks

S(Ks)

SCET

Williamson-Zupan

QCDF

Buchalla-Hiller-Nir-Raz

QCDF

Beneke

QCDF+FSI

Cheng-Chua-Soni


Rare B decays There are many rare decay processes sensitive to new physics effects. Electroweak penguin processes offer several theoretical clean observables.

Inclusive and exclusive b->s Inclusive and exclusive b->dInclusive and exclusive b->sll

1. Direct CP violation in b->sd

2. Mixing-induced CP asymmetry in B->K*Ks0

3. Lepton forward-backward asymmetryin b ->sll.

(New phase)

(Right-handed photon operator)


B

K*

l+

l-

Many recent theoretical developments are reported.

• Status of NNLLQCD correction to b->sg, b->sll. (T.Hurth)• Inclusive b->ul, b->sB->VV in SCET. (T.Feldmann)• B->K in SCET.(S.Jaeger) • Correction to mixing-induced CP violation in B->K*, Ks0. Naively the asymmetry is suppressed by ms/mb (a few %), but there are corrections at 10 % level in the SM. (B.Grinstein and D.Pirjol)• Forward Backward Asymmetry in B->K*l+l-

QCDF calculation (M.Beneke,T.Feldmann,and D.Seidel) SCET calculation (A.Ali,G.Kramer and G.Zhu)

A.Ali,G.Kramer and G.Zhu


Tauonic B decayThe Belle result of the B branching ratio.

This is sensitive to the charged Higgs boson exchange diagram in 2 Higgs doublet model as well as SUSY models. New contributions are important for the large tan case

H-b

u

Charged Higgs exchange contribution depends on

=> R.Barlow’s talk

b

u

W

439.056.046.049.0 10)79.1()(BF

B (Preliminary)


B(b->) vs. B(b->c) and B(B->D) Related modes are inclusive and exclusive proces

ses on b->c . Inclusive B(b->c) was measured at LEP

Y.Grossman, H.Haber and Y.Nir 1995

B(B->)

B(B->D)/B(B->D)

Two-fold ambiguity is not resolved by the Inclusive mode. Exclusive modes are necessary. H.Itoh,N.Gaur, Y.O

LEP

Belle ICHEP06Constraint on “r” in 2HDM.B(b->c)/B(b->ce)


Comparison with the charged Higgs boson production at LHC

•The parameter region coveredby B decays and the charged Higgs production overlaps.•If both experiments find positive effects, we can perform Universality Test of the charged Higgs couplings.

B-> H-b-u coupling B->D H-b-c couplinggb->tH: H-b-t coupling

K.A.Assamagan, Y.Coadou, A.Deandrea

Belle B->excluded region(95.5%CL)

Hb

t

t

g

SUSY loop vertex correction can break the universality.

K.A.Assamagan, Y.Coadou, A.Deandrea


Bs physics

This is a year of the Bs mixing.

Bs is quite different from Bd Large mass difference: (ms/md~40) Sizable life-time difference: s/s ~0(10%) Almost no CP phase in the Bs mixing amplitude in the SM.

Y.Grossman,Y.Nir,and G.Raz

If new physics effects induce a CP phase inthe Bs mixing amplitude:

Large time-dep CP asymmetry in B->J/(S)<SM) Correlation between semi-leptonic asymmetry (ASL) and S.

Z.Ligeti,M.Papucci, and G.PerezS

ASL


Bs mixing and New Physics: SUSY

•Supersymmetry introduces squarks and sleptons. •Squark mass matrixes can carry information on SUSY breaking mechanism and GUT scale interactions.•Quark flavor changing neutral current processes are sensitive to the off-diagonal elements of the squark mass matrix.


SUSY GUT and Bs mixing

SM

T.Goto,Y.O.Y.Shimizu,Y.Shindou,and M.Tanaka,2003

B() vs. ms/md in SUSY GUT

B.Dutta and Y.Mimura, hep-ph/0607147

SUSY GUT + Seesaw neutrino


Bs mixing and New Physics: Little Higgs model

•Little Higgs model : a model with a composite Higgs boson.

•New particles (heavy gauge bosons, a heavy top partner) are introduced to cancel the quadratic divergence of the Higgs mass at one loop level. •The mass of these particles are around 1 TeV if the model is extended with “T parity”.

•The lightest T-odd particle is a dark mattercandidate.

~10 TeV, new strong dynamics

~ 1TeV

WH, ZH, ij, uH,dH

AH

T+,T-

~200 GeV

A Higgs boson and SM particles

Particle content of the littlestHiggs model with T parity.

N.Arkani-Hamed,A.G.Cohen, E.Katz,and A.E.Nelson,2002

C.H.Cheng and I.Low,2003


Flavor signals of T-odd fermionsT-odd SU(2) doublet mirror fermions

Three flavor mixing matrixesTwo are independent.

d

u

W

VCKM

u

qH

WH,ZH,AH

VHu

d

qH

WH,ZH,AH

VHd

A new flavor mixing matrix can generatevarious patterns of deviation from the SM.

M.Blanke,A.J.Buras,A.Poschenrieder,C.Tarantino,S.Uhlig,and A.Weiler

J.Hubisz,S.J.Lee, and G.Paz


Bsand SUSY SUSY loop corrections can enhance B

(Bs->) by a few orders of magnitude from the SM prediction for large values of tan .

Loop-induced neutral Higgs exchange effects

sb

The discovery regionof a neutral Higgs bosonthrough pp->b0->bat LHC and the discovery region of Bs-> atTevatron and LHC overlap.

C.Kao and Y.Wang


Future of Kaon phyiscs

New limit2.1X10-7

(KEK E391)based on1/10 of Run I data

K0->0

A.Ceccuci

M.Doroshenko K

L 　 KEK E391=> JPARC JPARC-P14

K CERN-SPSC-P-326 (a.k.a. NA48/3)

JPARC-P09 Transverse polarisation in K (T-Violation )

JPARC-P06 Other Initiatives:

DANAE (Frascati) OKA (Protvino)

65 signal, 9±3Bgds/year


B physics at LHC

LHCb 2fb-1 T.Ruf

ATLAS T.Sivoklokov

CMS U.Langenegger

Much improvements are expected for Bs physics and B->K* measurements, etc.


Super B factory

5/ab 50/ab

In many aspects asymmetric B factoriesare complementary toB physics in hadron machine (unique forneutrino and tau modes)

Super KEK LoI

Current Belle+BaBar integratedluminosity: L(now)~1/ab

5X L(now) 50X L(now)


Pattern of New Physics effects

SUSY

Large Extra Dimensionmodel

Different pattern of the deviations from the SM prediction.Correlation with other physics observables.

2003 SLAC WS Proceedings


Summary

B factory experiments continue to produce interesting results.

Measurement of the Bs mixing have added a new dimension to flavor physics.

All these developments are important to explore physics beyond the Standard Model from the aspects of quark flavor physics in the LHC era.

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CP violation and CKM (Theory)

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