Semileptonic Decays of B Meson Transition Into D-wave Charmed Meson Doublets

Abstract

We use QCD sum rules to estimate the leading-order universal form factors describing the semileptonic B decay into orbital excited $D$-wave charmed doublets, including the ($1^{-}$, $2^{-}$) states ($D_1^{\ast }$, $D_2^{\prime }$) and the ($2^{-}$, $3^{-}$) states ($D_2$, $D_3^{\ast }$). The decay rates we predict are ${\Gamma }_{B\to D_1^{\ast }\ell \overline{\nu }}={\Gamma }_{B\to D_2^{\prime }\ell \overline{\nu }}=2.4\times 10^{-18}GeV$, ${\Gamma }_{B\to D_2\ell \overline{\nu }}=6.2\times 10^{-17}GeV$, and ${\Gamma }_{B\to D_3^{\ast }\ell \overline{\nu }}=8.6\times 10^{-17}GeV$. The branching ratios are $\mathcal{B}(B\to D_1^{\ast }\ell \overline{\nu })=\mathcal{B}(B\to D_2^{\prime }\ell \overline{\nu })=6.0\times 10^{-6}$, $\mathcal{B}(B\to D_2\ell \overline{\nu })=1.5\times 10^{-4}$, and $\mathcal{B}(B\to D_3^{\ast }\ell \overline{\nu })=2.1\times 10^{-4}$, respectively.

Comments: 11 pages, 3 figures