Flavor Phenomenology in SUSY models Yasuhiro Okada (KEK/Sokendai) September 26, 2007 4th ICFP, KITPC, Beijing with Toru Goto, Tetsuo Shindou, and Minoru Tanaka

Flavor physics in the LHC era The LHC experiment will start to look at the TeV scale physics directly next year. Past and ongoing experiments in flavor physics have already put strong constraints on new physics models. (KEK and SLAC B factories, Tevatron B physics, etc.) Several new experiments are under construction, LHCb(B), BESIII(t,charm),MEG(m->eg), and future plans of Super B factory are considered at KEK and Frascati.

Energy frontier vs. flavor 0.001 0.01 0.1 1 10 Energy scale Coupling strength LHC Tevatron 100 TeV Upgraded KEKB If new particles are discovered at LHC, flavor physics can determine couplings, mixings, and CP phases related to new phenomena, or restrict possible scenarios.

Lepton flavor violation SUSY and Favor Slepton and squark mass matrixes are a window to SUSY breaking mechanisms and GUT scale interactions. GUT Yukawa coupling Neutrino Yukawa Coupling Squark/slepton mass matrixes Origin of SUSY breaking SUSY spectrum Quark favor signals Lepton flavor violation We can explore the fundamental structure of SUSY models at high scales from quark and lepton flavor signals

LHC/ILC vs. Quark Flavor Signals/LFV Squark/slepton mass matrix Quark flavor changing processes LHC: Squark up to ~3 TeV. Diagonal Off-diagonal Lepton flavor violation LHC+ILC: Squark/slepton mass spectrum

B physics in three SUSY models T.Goto, Y.O. Y.Shimizu, T.Shindou, and M.Tanaka, PRD(2002), (2004) In order to illustrate how B physics is useful to distinguish different SUSY models, we calculated various quark flavor observables in three representative SUSY models. Models 1. Minimal supergravity model (mSUGRA) 2. SU(5) SUSY GUT with right-handed neutrino MSSM with U(2) flavor symmetry Observables Bd-Bd mixing, Bs-Bs mixing. CP violation in K-K mixing (e). Time-dependent CP violation in B ->J/yKs, B->fKs, B->K*g . Direct CP violation in b->s g.

A new study on quark and lepton flavor signals in SUSY models T.Goto, Y.O.T.Shindou, and M.Tanaka, 2007 We have extended our previous work in the light of new developments and prospects of future experimental programs. 1. Bs physics We take the Bs mixing as a new constraint, and calculate time-dependent CP asymmetry in Bs-> J/y f mode, which is expected to be measured up to the precision of 0.01 at LHCb. (CDF,2006) 2. Tau LFV We have calculated t -> mg and t -> eg branching ratios in addition to m->eg for models with right-handed neutrinos. Current bounds are ~10-7 but 1-2 orders of improvements are possible at a future Super B factory, 3. Several technical improvements for calculations are incorporated.

mSUGRA and neutrino and GUT Yukawa couplings We consider: mSUGRA model, MSSM with the right-handed neutrinos, SU(5) SUSY GUT with right-handed neutrinos. Quark and neutrino Yukawa couplings are sources of squark and slepton flavor mixings. Flavor univesrality of SUSY breaking terms at the cutoff scale Quark FCNC LFV Quark Yukawa coupling Neutrino Yukawa coupling Yq Yn Neutrino seesaw model mSUGRA GUT L.J.Hall,V.Kostelecky,S.Raby,1986;A.Masiero, F.Borzumati, 1986

Neutrino Yukawa coupling and LFV LFV constraint depends on neutrino parameters Neutrino mass LFV mass terms for slepton (and sdown). Three cases are considered for MR. Degenerate case (MR )ij= M dij Severe m->eg constraint Non-degenerate (I) Non-degenerate (II) m ->eg suppressed (Casas and Ibarra, Ellis-Hisano-Raidal-Shimizu)

MSSM with U(2) flavor symmetry 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; …. 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 We do not consider LFV processes in this model

Lepton flavor violation processes in SU(5) SUSY GUT with right-handed neutrinos m->eg, t->mg,t->eg rates are calculated in three cases in the GUT model. Degenerate Non-degenerate (I) Non-degenerate (II) t->eg t->mg m->eg slepton mass 3TeV

t->mg and m->eg can be close to the present bounds We take MR= 4x1014 GeV, which corresponds to 0(1) neutrino Yukawa coupling constants. Degenerate case: B(m->eg) is the process that limits the SUSY parameter space, and can be close to the present bound even if the slepton mass is 3 TeV. Non-degenerate (I) t->mg and m->eg can be close to the present bounds Non-degenerate (II) t->eg and m->eg can be close to the present bounds. m->eg vs. tLFV in non-degenerate (I)

b-s and b-d transition processes We have calculated the following observables for mSUGRA, three cases of SUSY GUT with RHN, and the U(2) model. S(K*g): Mixing-induced CP asymmetry of B->K*g S(rg): Mixing-induced CP asymmetry of B->rg A(sg): Direct CP asymmetry of b->sg A(dg): Direct CP asymmetry of b->dg DS(fKs)=S(fKs)-S(J/yKs): Difference of mixing-induced asymmetries for B->fKs and B->J/yKs S(Bs->J/yf): Mixing-induced asymmetry of Bs->J/yf Chiral structure New phase Phase of the Bs mixing amplitude, ~-0.04 in the SM New CP phase We have taken account of constraints from LFV and EDM searches.

Mixing-induced CP asymmetry: S(B->K*g) U(2) model SUSY GUT non-deg (I) mSUGRA Super B sdown mass 3 TeV Deviation can be large in SUSY GUT non-deg(I) and U(2) case Expected precision is 0.02-0.03 at Super B factory. Estimation of experimental reach from Super KEKB LOI, SuperB:CDR, CERN WS on Flavour in the era of the LHC

Mixing-induced CP asymmetry: S(B->rg) mSUGRA SUSY GUT non-deg (II) U(2) model Super B Expected precision is 0.08-0.12 at Super B factory.

Direct CP Asymmety: A(b->sg) mSUGRA SUSY GUT non-deg (I) U(2) Super B Some deviations from the SM in the U(2) case. Precision will be 0.004-0.005 at Super B factory.

DS(fKs)=S(B->fKs)-S(B->J/yKs) mSUGRA SUSY GUT non-deg (I) U(2) model Super B Expected precision is 0.02-0.03 at Super B factory.

S(Bs->J/yf) for a new CP phase in the Bs mixing amplitude SUSY GUT non-deg (I) U(2) model mSUGRA LHCb Expected precision is 0.01 at LHCb from talk by T.Nakata at “SUSY 2010’s”, Hokkaido Univ. June 2007.

Correlation between DmBs/DmBd and f3(g) of the Unitarity triangle Present precision of f3 from tree processes If the f3 angle is precisely determined by tree processes, we can extract new physics contributions in DmBs/DmBd with improved determination of the hadronic factor　(x2 =fBs2 BBs/fBd2 BBd) by lattice QCD. Precision of f3 determination is 2.4 deg at LHCb and 1-2 deg at Super B factory.

DmBs/DmBd vs. f3 U(2) model mSGURA SUSY GUT non-deg (II) LHCb Correlation in mSUGRA is the same as in the SM . The error in the vertical axis is essentially the uncertainty of x. This is a sensitive test for new physics contributions to Bs and Bd mixing amplitudes unless they are cancelled as in the case of Minimal Flavor Violation.

Pattern of new physics signals Promising signals Possible deviations for some points Pattern of deviations from the SM can provide a clue on physics determining the structure of the SUSY breaking sector.

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. Bs physics at LHCb and tau LFV searches at a future B factory will be important parts of this program, along with the m->eg search at the MEG experiment.