The asymmetries of the $B\to K^{\ast }\hat{I}{¼}^{+}\hat{I}{¼}^{-}$ decay and the search of new physics beyond the Standard Model

Abstract

In this paper, we compute the forward-backward asymmetry and the isospin asymmetry of the $B\to K^{\ast }\hat{I}{¼}^{+}\hat{I}{¼}^{-}$ decay. The $B\to K^{\ast }$ transition form factors (TFFs) are key components of the decay. To achieve a more accurate QCD prediction, we adopt a chiral correlator for calculating the QCD light-cone sum rules for those TFFs with the purpose of suppressing the uncertain high-twist distribution amplitudes. Our predictions show that the asymmetries under the Standard Model and the Minimal Supersymmetric Standard Model with minimal flavor violation are close in shape for $q^2\ge 6{\mathrm{GeV}}^2$ and are consistent with the Belle, LHCb and CDF data within errors. When $q^2<2{\mathrm{GeV}}^2$, their predictions behave quite differently. Thus a careful study on the $B\to K^{\ast }\hat{I}{¼}^{+}\hat{I}{¼}^{-}$ decay within small $q^2$-region could be helpful for searching new physics beyond the Standard Model. As a further application, we also apply the $B\to K^{\ast }$ TFFs to the branching ratio and longitudinal polarization fraction of the $B\to K^{\ast }\hat{I}½\bar{\hat{I}}½$ decay within different models.

11 pages, 6 figures, references updated and revised version to be published in Phys. Rev. D