Second-order direct CP asymmetry in B ( s ) → X ? ν

摘要

A direct CP asymmetry in inclusive semileptonic B ( s ) decays vanishes by CPT to lowest order in weak interactions. Calculating the asymmetry at second-order-weak interactions in the Cabibbo–Kobayashi–Maskawa framework we find A s l = ( ? 3.2 ± 0.9 ) × 10 ? 9 . A maximal asymmetry which is two orders of magnitude larger is estimated in a left–right-symmetric model. This quite generic upper bound implies negligible effects on wrong-sign lepton asymmetries in B 0 and B s decays.