Exploring Flavor Structure of Supersymmetry Breaking at B factories

We investigate flavor physics at present and future B factories in order to distinguish supersymmetric models. We evaluate CP asymmetries in various B decay modes, Delta M(Bd), Delta M(Bs), and epsilon_K in three supersymmetric models, i.e. the minimal supergravity, the SU(5) SUSY GUT with right handed neutrinos, and a supersymmetric model with U(2) flavor symmetry. The allowed regions of Delta M(Bs)/Delta M(Bd) and CP asymmetries in B to J/psi K_S and b to s gamma are different for the three models so that it is possible to distinguish the three models by precise determinations of these observables in near future experiments.