The Semileptonic $B$ to $K_1(1270,1400)$ Decays in QCD Sum Rules

Abstract

We analyze the semileptonic rare decays of $B$ meson to $K_1(1270)$ and $K_1(1400)$ axial vector mesons. The $B\to K_1(1270,1400){\ell }^{+}{\ell }^{-}$ decays are significant flavor changing neutral current decays of the $B$ meson. These decays are sensitive to the new physics beyond SM, since these processes are forbidden at tree level at SM. These decays occurring at the quark level via $b\to s{\ell }^{+}{\ell }^{-}$ transition, also provide new opportunities for calculating the CKM matrix elements $V_{bt}$ and $V_{ts}$. In this study, the transition form factors of the $B\to K_1(1270,1400){\ell }^{+}{\ell }^{-}$ decays are calculated using three-point QCD sum rules approach. The resulting form factors are used to estimate the branching fractions of these decays.

Comments: 18 pages, 7 figures, version to appear in JPG