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Exploring SUSY models through quark and lepton flavor physics

Yasuhiro Okada(KEK/Sokendai)

June 18, 2008

SUSY 2008, Seoul, Korea

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Content of this talk

Quark and lepton flavor physics processes sensitive to the TeV scale physics.

Study of quark and lepton flavor signals in various cases of SUSY models.

　　　　　　　　　　　 T.Goto,Y.O., T.Shindou,M.Tanaka, arXiv:0711.2935

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Flavor in the LHC era

LHC will give a first look at the TeV scale physics. 　 The mass of the Higgs boson alone is an important hint for possi

ble new physics scenarios. Flavor structure of the TeV scale physics is largely u

nknown.　 Patterns of the deviations from the SM predictions are a key to

distinguish new physics models. New flavor experiments are coming. LHCb, B physic

s at ATLAS and CMS, MEG, Super B, etc.

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Quark flavor

B,D,K

Lepton flavorNeutrino mixing

LFV~0

EDM ~0

Relationship may be quite different for new physics contributions.

GUT

SUSY CP

slepton mixing

SM has a characteristic feature among various flavor and CP signals.

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The Unitarity Triangle Even if CKM looks　 perfect, there are still room for new　 physics contributions of at least a few 10’s %.

Fit by tree level processes SM global fit

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|Vub|,

Bd mixing and CP asymmetries

K and B(K)

Bs mixing and CP asymmetries

+

+

+

In order to disentangle new physics effects, we first need todetermine the CKM parameter by tree processes.

We know (or constrain) which sector is affected by new physics

Expected precision LHCb 5-10 deg (2fb-1: 1year)

Super B factory1-2 deg (50-75 ab-1)

Improvement on 3/ is essential

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Rare B decays: Various tests of new physics

S(B->Ks)

Time-dependent CP asymmetry of penguin-dominated processes

A(b->s)

Direct CP asymmetry of b->s S(B->K*)

Time-dependent CP asymmetry of B-> K*

AFB(b->sll), AFB(B->K*g)

Forward-backward asymmetry of b->sll, B->K*ll

B(B->,B(B-> D

New phase

New phase

Right-handed operator

H-b

u

charged Higgs exchange

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Expected precisions at Super B factory

CERN Flavour WS report: arXiv:0801.1833   

Super KEKB study and SuperB CDR study; 50-75 ab-1

b-s transition

EW penguin

Charged Higgs

0(10%) physics (Now)=> 0(1%) physics (Future)

0.39 ± 0.17 0.61 ± 0.07 0.58 ± 0.20

−0.09 ± 0.24

error ~0.05-0.06

Current results

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CPV in Bs system at LHCb Measurement of CP violation in the Bs system is a

major goal of the LHCb experiment. Many are parallel to the Bd system.

S(Bd->J/ Ks)

S(Bd->Ks)

S(Bd->K*)

Time dep. CP in Bs->J/ “Bs mixing phase”

Time-dep. CPV in Bs-> “b-s penguin phase”

Time-dep. CPV in Bs->“right-handed current”

M.Merk,a talk at CERM TH Institute, May 26,20082fb-1 (1year)

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and Lepton Flavor Violation Sensitive to slepton flavor mixings

The MEG experiment will search for B(->e) up to 10-13. The current upper bound is 1.2 x 10-11.

One to two orders improvements are expected at a Super B factory for tau LFV searches.

S.Banerjee, TAU 06

B( )

Super B factory, 50-75 ab-1 arXiv:0801.1833   

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SUSY and flavor physics LHC experiments will be a crucial test for existence of S

USY. (Squark/gluino mass reach 2-3 TeV, A light Higgs boson)

The role of flavor physics is to determine the flavor structure of squark/slepton mass matrixes. (new sources of flavor mixing and CP phases)

Squark/slepton mass matrixes carry information of SUSY breaking mechanism and interactions at high energy scale (ex. GUT/Planck scale).

Diagonal tem: LHC/LCOff diagonal term: Flavor Physics

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Different assumptions on the SUSY breaking sector

SUSY breaking

Minimal Flavor Violation (ex. mSUGRA)

SUSY GUT with see-saw neutrinos

Flavor symmetry

Effective SUSY

etc.

How to distinguish these models from factory observables?

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Quark and lepton flavor physics in various SUSY models In order to illustrate how future flavor experiments are

useful to distinguish different SUSY models, we calculated various quark and lepton flavor observables in representative SUSY models.

Models

1. Minimal supergravity model (mSUGRA)

2. SUSY seesaw model

2. SU(5) SUSY GUT with right-handed neutrino

3. MSSM with U(2) flavor symmetry

Observables Bd-Bd mixing, Bs-Bs mixing. CP violation in K-K mixing (). Time-dependent CP violation i

n B ->J/Ks, B->Ks, B->K* ,B->.

Direct CP violation in b->s ,b->d

->e, ->, ->e

T.Goto, Y.O. Y.Shimizu, T.Shindou, and M.Tanaka,2002, 2004

T.Goto,Y.O., T.Shindou,M.Tanaka, arXiv:0711.2935

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mSUGRSA with GUT/Seesaw Yukawa interaction

Quark Yukawa coupling Neutrino Yukawa coupling

Interactions at GUT/seesaw scale

Quark flavor signalsTime-dep CP asymmetries in

B->Ks B -> K*Bs->J/

Lepton flavor violation in->e->->e

L.J.Hall,V.Kostelecky,S.Raby,1986;A.Masiero, F.Borzumati, 1986, R.Barbieri,L.Hall,1994, R.Barbieri,L.Hall.A.Strumia, 1995, S.Baek,T.Goto,Y.O, K.Okumura, 2001;T.Moroi,2000; A.Masiero, M.Piai,A Romanino, L.Silvestrini,2001 D.Chang, A.Masiero, H.Murayama,2003J.Hisano,and Y.Shimizu, 2003, M.Ciuchini, et.al, 2004, 2007…

Yukawa interactions at the GUT scales induce quark and lepton flavor signals. In the SU(5) setup, the right-handed sdown sector can receive flavor mixing due to the neutrino Yukawa couplings.

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Neutrino mass matrix (in the basis where yl is diagonal).

LFV mass terms for slepton (and sdown).

Effects of the neutrino Yukawa coupling

LFV mass terms and VPMNSis directly related when

(Minimal LFV)

Large solar mixing angle=> >eenhanced

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If is somewhat suppressed, the B(->e) constraint becomes weaker, and a variety of flavor signals are possible.

• Non-degenerate MN

• Degenerate MN, but inverse hierarchy or degenerate light neutrino with 13~0.

J.Casas, A.Ibarra2001; J.Ellis,J.Hisano,M.Raidal,Y.Shimizu, 2002

We consider various cases for heavy neutrino and light neutrino mass hierarchy.

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SUSY Seesaw model (without GUT)

Normal hierarchy Inverse hierarchy Degenerate (m1=0.1eV)

-ee

Degenerate MN (=4x1014 GeV)13 =0

Recent related works: L.Calibim, A.Faccica A.Masiero, S.K.Vepati, 2006L.Calibim, A.Faccica A.Masiero, 2006

-eis promising signal in the normal hierarchy case, and >can be alsolarge in other cases :

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Degenerate MN and “Normal hierarchy” for light neutrinos :

e) can be close to thepresent bound even if the slepton mass is 3 TeV.

Contour in the m0 -M1/2 plane

ebound

e, >e branching ratios

SU(5) SUSY GUT

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, evs. e

Lepton Flavor Violation in the non-degenerate MN case

B(e

B(

e

e

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S(Bd->K*S= S(B->Ks)-S(B->J/Ks)

These asymmetries can be sizable if the squarks are within the LHC reach.

Time-dependent CP violation in Bd decays

Super BSuper B

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S(Bs->J/ S(Bs->J/Ks) vs. B(->)

Recent works on Bs mixing:J.K. Parrym H-H. Zhong 2007; B.Dutta, Y.Mimura2008; J.Hisano Y.Shimizu, 2008.

LHCb

SuperB

Time-dependent CP asymmetry in Bs -> J/

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MSSM with U(2) flavor symmetry The quark Yukawa couplings and the squark mass

terms are governed by the same flavor symmetry. 1st and 2nd generation => U(2) doublet 3rd generation => U(2) singlet

A.Pomarol and D.Tommasini, 1996; R.Barbieri,G.Dvali, and L.Hall, 1996; R.Barbieri and L.Hall;R.Barbieri, L.Hall, S.Raby, and A.Romonino; R.Barbieri,L.Hall, and A.Romanino 1997; A.Masiero,M.Piai, and A.Romanino, and L.Silvestrini,2001; ….

We do not consider LFV processes in this model

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A( b->s

S(Bs->J/S(Bd->

S(Bd->K*

Various CP asymmetries are possible for the b-s and b-d transitions in the U(2) model

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Summary table of flavor signals for mSUGRA, SUSY seesaw, SUSY GUT, MSSA with U(2) flavor symmetry

LFV

b-s and b-d transitions

Pattern of deviation from the SM predictions are different for various cases considered.

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Conclusions

We have performed a comparative study on quark and lepton flavor signals for representative SUSY models; mSUGRA, MSSM with right-handed neutrinos, SU(5) SUSY GUT with right-handed neutrinos, and U(2) models.

Each model predicts a different pattern of the deviations from the SM in b-s and b-d quark transition processes and muon and tau LFV processes.

These signals can provide important clues on physics at very high energy scales if SUSY particles are found at LHC.