B. Dutta Texas A&M University Phys.Rev.Lett.100:181801,2008; arXiv: ; To appear Grand Unified Models, Proton Decay and Phase of Collaborator: Yukihiro Mimura ICHEP 08

Large FCNCs exist for general SUSY breaking masses. Flavor universality of SUSY breaking is assumed to solve the flavor problem. FCNCs can still be induced by RGEs. In MSSM, the quark FCNCs are small due to small CKM mixings. If there is a heavy particle, e.g., heavy right handed neutrino, the loop corrections can induce sizable FCNCs due to large neutrino mixing. (Borzumati-Masiero) Flavor Violation in Grand Unified Models The flavor violation effects teach us GUT scale physics Introduction

and are correlated. In this talk : In GUT models, (Belle) The phase of. Is also restricted We will study large CP phase in SU(5) and SO(10) GUT models. The nature of FCNC and CP violation is very important to test the existence of new physics FCNC and New Physics Dutta, Mimura, Phys.Rev.Lett.97:241802,2006.

Large Phase of CP violation in Measurements : SM prediction : small! 2.2 sigma deviation from the SM (arXiv: ) (arXiv: ) Combined data analysis by UTfit: More than 3 sigma deviation from the SM arXiv:

The gluino box diagram dominates. Mass insertion approximation: b s sb (Ball-Khalil-Kou)

However, experimental result of does not constrain size of SUSY contribution much. Accurate measurement of mass difference is consistent with SM. There is room for a sizable SUSY contribution. One may think that large SUSY contribution is not allowed. New Physics Contribution in the Mixing Due to free phases in the Yukawa coupling [Tevatron] What is this large SUSY contribution?

SU(5) GUT Down quarks and lepton doublet are unified in Right-handed neutrino : Both RH down-squarks and LH sleptons can have FCNC effects. (Moroi, Akama-Kiyo-Komine-Moroi, Baek-Goto-Okada-Okumura, …)

U is the MNS neutrino mixing matrix. SU(5) GUT… The flavor violating elements in m 2 5 induces B s mixing

Sparticle spectrum is restricted. LHC SU(5) GUT…

22 11 in B s mixing

Stau coannihilation region Higgsino dark matter region

Both left- and right-squarks have FCNC effects in SO(10). Flavor violating effects are larger in the box diagram in SO(10). SO(10) GUT

In the SO(10) model, can be large due to left-right box enhancement. can be suppressed by a choice of vacua. If (8,2,1/2) (in 126 Higgs) is light, it generates FCNC in the quark sector For example, Light (8,2,1/2) is needed to suppress proton decay. (Dutta-Mimura-Mohapatra, Phys.Rev.Lett.100:181801,2008. ) SO(10) GUT… (8,2,1/2) introduces flavor violation only in the squark sector

If is suppressed by a choice of the vacua, constraint is important. However, can be adjusted to be the experimental range unless is enhanced too much by gluino contribution. (this requires small left-right mixing for sbottom) Direct CP violation of can be large for large

Large Tan  h 0, H 0, A 0 bRbR sLsL bRbR sLsL Double penguin diagram can have large Contribution This diagram’s contribution (~    tan 4  /M A 4 ) Similar single penguin diagrams contribute to B s   process (~  2 tan 6  /M A 4 ) Large B s phase induces larger B s   process even for tan  ~20 for universal boundary condition Both SU(5) and SO(10) get contribution from this diagram Chargino and gluino mediated penguins contribute

Conclusion We study the bound of from the LFV in SUSY GUT models. SUSY spectrum is restricted in SU(5) model where Dirac neutrino is the origin of the large phase. SO(10) models can generate larger phases. We expect further accurate experiments to learn more about the GUT scale physics from the

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(95%) (UTfit)