Probing the extended Higgs sector through rare b -> s mu(+)mu(-) transitions

Abstract

We study the constraints on the contribution of new physics in the form of scalar/pseudoscalar operators to the average forward-backward asymmetry < A(FB)> of muons in B -> K mu(+)mu(-) and the longitudinal polarization asymmetry A(LP) of muons in B(s)->mu(+)mu(-). We find that the maximum possible value of < A(FB)> allowed by the present upper bound on B(B(s)->mu(+)mu(-)) is about 1% at 95% C.L. and hence will be very difficult to measure. On the other hand, the present bound on B(B(s)->mu(+)mu(-)) fails to put any constraints on A(LP), which can be as high as 100% even if B(B(s)->mu(+)mu(-)) is close to its standard model prediction. The measurement of A(LP) will be a direct evidence for an extended Higgs sector, and combined with the branching ratio B(B(s)->mu(+)mu(-)) it can even separate the new physics scalar and pseudoscalar contributions.