Large Phase of B_s-\bar B_s Mixing in Supersymmetric Grand Unified Theories

We consider the possibility of a large phase of B_s-\bar B_s mixing in supersymmetric SU(5) and SO(10) models. We find that in the SU(5) model, the magnitude of this phase is correlated with the branching ratio of \tau -> \mu\gamma and the phase can be within 2\sigma of the recent UTfit analysis. In the case of SO(10) models, this correlation can be relaxed and a large phase can be obtained. In this scenario, a non-zero value of CP asymmetry for B -> X_s\gamma will be predicted. We predict the sparticle mass ranges for the LHC for these models once the UTfit result is accommodated and discuss the dark matter and the anomalous magnetic moment constraints on this analysis.Comment: 5 pages, 3 figure

Enhancement of Br(B_d -> mu^+mu^-)/Br(B_s -> mu^+mu^-) in Supersymmetric Unified Models

We explain the 2.3 sigma deviation in the recent measurements of the neutral B mesons decay into muon pairs from the standard model prediction in the framework of supersymmetric grand unified models using anti-symmetric coupling as a new source of flavor violation. We show a correlation between the B_d -> mu^+mu^- decay and the CP phase in the B_d -> J/psi K decay and that their deviations from the standard model predictions can be explained after satisfying constraints arising from various hadronic and leptonic rare decay processes, B-bar{B}, K-bar{K} oscillations data and electric dipole moments of electron and neutron. The allowed parameter space is typically represented by pseudoscalar Higgs mass m_A < 1 TeV and tan beta_H (= {v_u}/{v_d}) < 20 for squark and gluino masses around 2 TeV.Comment: 6 pages, 3 figure

B(s)-B(s)bar Mixing in Supersymmetric Grand Unified Models

We study B_s-\bar{B}_s mixing in grand unified SO(10), SU(5) models where the mixings among the second and third generation squarks arise due to the existence of flavor violating sources in the Dirac and Majorana couplings which are responsible for neutrino mixings. We find that when the branching ratio of tau->mu gamma decay is enhanced to be around the current experimental bound, B_s-\bar{B}_s mixing may also contain large contribution from supersymmetry in the SO(10) boundary condition. Consequently, the phase of B_s-\bar{B}_s mixing is large (especially for small tan beta and large scalar mass m_0) and can be tested by measuring CP asymmetries of B_s decay modes.Comment: 5 pages, 3 figures. Modifications in the text and the title, references added, results unchanged, to appear in PR