$(g-2{)}_{\mu }$ and CP Asymmetries in $B_{d,s}^0\to l^{+}{l}^{-}$ and $b\to s\gamma$ in SUSY models

Abstract

We show that with a good fit to the muon $g-2$ constraint, the CP asymmetry can be as large as 25% (15%) for $B_d^0\to {\tau }^{+}{\tau }^{-}$ ($B_d^0\to {\mu }^{+}{\mu }^{-}$) in SUGRA models with nonuniversal gaugino masses and MSSM. If tau events indentified at B factories the CP asymmetry in $B_d^0\to {\tau }^{+}{\tau }^{-}$ can be a powerful probe on physics beyond SM. An interesting case is that new physics gives a prediction on the branching ratio which is still in the uncertain region of the SM prediction. The CP asymmetry for $B_d^0\to l^{+}{l}^{-}$ in this case can still reach 20%. So it is powerful to shed light on physics beyond SM while the CP asymmetry of $b\to s\gamma$ in this case can only reach 2% at most which is too small to draw a definite conclusion on new physics effects at B factories.

Comments: discussions extended, version to appear in PLB