CP asymmetry in B --> phi K_S decays in left-right models and its implications on B_s decays

Abstract

In left-right models the gluonic penguin contribution to b --> s s-bar s transition is enhanced by m_t/m_b due to the presence of (V+A) currents and by the larger values of loop functions than in the Standard Model. Together those may completely overcome the suppression due to small left-right mixing angle xi <~ 0.013. Two independent new phases in the B --> phi K_S decay amplitude appearing in a large class of left-right models may therefore modify the time dependent CP asymmetry in this decay mode by O(1) and explain the recent BaBar and Belle CP asymmetry measurements in this channel. This new physics scenario implies observable deviations from the Standard Model also in B_s decays which could be measured at upcoming Tevatron and LHC.