SemileptonicBq→Dq*lν(q=s,d,u)decays in QCD sum rules

Abstract

The form factors relevant to ${B}_{q}\ensuremath{\rightarrow}{D}_{q}^{*}({J}^{P}={1}^{\ensuremath{-}})\ensuremath{\ell}\ensuremath{\nu}$ ($q=s$, $d$, $u$) decays are calculated in the framework of the three point QCD sum rules approach. The heavy quark effective theory prediction of the form factors as well as $1/{m}_{b}$ corrections to those form factors are obtained. A comparison of the results for the ratio of form factors at zero recoil limit and other values of ${q}^{2}$ with the predictions of the subleading Isgur-Wise form factor application for $B\ensuremath{\rightarrow}{D}^{*}\ensuremath{\ell}\ensuremath{\nu}$ is presented. The total decay width and branching ratio for these decays are also evaluated using the ${q}^{2}$ dependencies of these form factors. The results are in good agreement with the constituent quark meson model and existing experimental data. The $q=s$ case can also be detected at LHC in the near future.