More benefits of semileptonic rare B decays at low recoil: CP violation

We present a systematic analysis of the angular distribution of (B) over bar -> (K) over bar* (-> (K) over bar pi)l(+)l(-) decays with l = e, mu in the low recoil region (i.e. at high dilepton invariant masses of the order of the mass of the b-quark) to account model-independently for CP violation beyond the Standard Model, working to next-to-leading order QCD. From the employed heavy quark effective theory framework we identify the key CP observables with reduced hadronic uncertainties. Since some of the CP asymmetries are CP-odd they can be measured without B-flavour tagging. This is particularly beneficial for (B) over bar (s,) B-s -> phi(-> K+K-)l(+)l(-) decays, which are not self-tagging, and we work out the corresponding time-integrated CP asymmetries. Presently available experimental constraints allow the proposed CP asymmetries to be sizeable, up to values of the order similar to 0.2, while the corresponding Standard Model values receive a strong parametric suppression at the level of O (10(-4)). Furthermore, we work out the allowed ranges of the short-distance (Wilson) coefficients C-9,C-10 in the presence of CP violation beyond the Standard Model but no further Dirac structures. We find the (B) over bar (s) -> mu(+)mu(-) branching ratio to be below 10 x 10(-9) (at 95% CL). Possibilities to check the performance of the theoretical low recoil framework are pointed out.