New physics effects on the CP asymmetries in B→φKS and B→η′KS decays -: art. no. 014020

Within the standard model (SM), the time-dependent CP asymmetries in B-->psiK(S), B-->eta'K-S, and B-->phiK(S) are expected to give the same result, i.e., sin 2beta. However, recent measurements of the mixing-induced CP asymmetries in B-->phiK(S) and B-->eta'K-S modes give results whose central values differ from the SM expectations. We explore the effect of new physics in the two Higgs doublet model (THDM), which allows tree level flavor changing neutral currents (so-called model III), and the model with an extra vectorlike down quark (VLDQ). We find that the observed mixing-induced CP asymmetry for B-->phiK(S) cannot be accommodated by the THDM but can be explained in the VLDQ model, and both models can explain the observed asymmetry for B-->eta'K-S mode.