Left-handed Z′ and Z FCNC quark couplings facing new b → sμ+μ- data

In view of the recent improved data on B-s,B-d -> mu(+)mu(-) and B-d -> K*mu(+)mu(-) we revisit two simple New Physics (NP) scenarios analyzed by us last year in which new FCNC currents in b -> s mu(+)mu(-) transitions are mediated either entirely by a neutral heavy gauge boson Z' with purely left-handed complex couplings Delta(qb)(L)(Z') (q = d, s) and real couplings to muons Delta(mu(mu) over bar)(A)(Z') and Delta(mu(mu) over bar)(V)(Z') or the SM Z boson with left-handed complex couplings Delta(qb)(L)(Z). We demonstrate how the reduced couplings, the couplings in question divided by M-Z' or M-Z, can be determined by future Delta F = 2 and b -> s mu(+)mu(-) observables up to sign ambiguities. The latter do not affect the correlations between various observables that can test these NP scenarios. We present the results as functions of C-Bq = Delta M-q/(Delta M-q)(SM), S-psi phi and S-psi KS which should be precisely determined in this decade. We calculate the violation of the CMFV relation between B (B-s,B-d -> mu(+)mu(-)) and Delta M-s,M-d in these scenarios. We find that the data on B-s,B-d -> mu(+)mu(-) from CMS and LHCb can be reproduced in both scenarios but in the case of Z, Delta M-s and S-psi phi have to be very close to their SM values. As far as B-d -> K*mu(+)mu(-) anomalies are concerned the Z' scenario can significantly soften these anomalies while the Z boson fails badly because of the small vector coupling to muons. We also point out that recent proposals of explaining these anomalies with the help of a real Wilson coefficient C-9(NP) implies uniquely an enhancement of Delta M-s with respect to its SM value, while a complex C-9(NP) allows for both enhancement and suppression of Delta M-s and simultaneously novel CP-violating effects. Correlations between b -> s mu(+)mu(-) and b -> s nu(nu) over bar observables in these scenarios are emphasized. We also discuss briefly scenarios in which the Z' boson has right-handed FCNC couplings. In this context we point out a number of correlations between angular observables measured in B-d -> K*mu(+)mu(-) that arise in the absence of new CP-violating phases in scenarios with only left-handed or right-handed couplings or scenarios in which left-handed and right-handed couplings are equal to each other or differ by sign.