Implications of new physics in B→K1μ+μ- decay processes

Abstract

Recently, several discrepancies at the level of (2-3)σ have been observed in the decay processes mediated by flavour changing neutral current (FCNC) transitions b→sl+l-, which may be considered as the smoking-gun signal of new physics (NP). These intriguing hints of NP have attracted a lot of attention and many attempts are being made to find the possible NP signature in other related processes, which are mediated through the same quark-level transitions. In this work, we perform a comprehensive analysis of the FCNC decays of the B meson to axial vector mesons K1 (1270) and K1 (1400), which are an admixture of the 13P1 and 11P1 states K1A and K1B, in a model independent framework. Using the B→K1 form factors evaluated in the light cone sum rule approach, we investigate the rare exclusive semileptonic decays B→K1 (1270)μ+ μ- and B→K1(1400)μ+μ-. Considering all the possible relevant operators for b→sl+l- transitions, we study their effects on various observables such as branching fractions, the lepton flavor universality violating ratio (RK1), forward-backward asymmetries, and lepton polarization asymmetries of these processes. These results will not only enhance the theoretical understanding of the mixing angle but also serve as a good tool for probing NP.