Can R-parity violation lower sin2β?

Abstract

Recent time-dependent CP asymmetry measurements in the B_d → J/ψK_S channel by the BaBar and Belle Collaborations yield somewhat lower values of sin2β compared to the one obtained from the standard model fit. If the inconsistency between these numbers persists with more statistics, this will signal new physics contaminating the B_d → J/ψK_S channel, thus disturbing the extraction of β. We show that the R-parity-violating interactions in supersymmetric theories can provide extra new phases which play a role in significantly reducing the above CP asymmetry, thus explaining why BaBar and Belle report lower values of sin2β. The same couplings also affect the B_d → φK_S decay rate and asymmetry, explain the B → η′K anomaly, and predict nonzero CP asymmetry in dominant B_s decays. The scenario will be tested in the ongoing and upcoming B factories.