S to P wave form factors in semi-leptonic B decays

We apply HQET to semi-leptonic $B$ and $B_{s}$ meson decays into the observed charmed $P$ wave states. In order to examine the sensitivity of the results to the choice of a specific model, we perform all calculations using several different meson models, and find that uncertainty introduced by the choice of a particular model is about 30\%. Specifically, assuming $\tau_{B}=1.50ps$ and $V_{cb}= 0.040$, we obtain branching ratios of $(0.27\pm 0.08)\%$ and $(0.45\pm 0.14)\%$ for $B\rar D_{1}l\bar{\nu}_{l}$ and $B\rar D_{2}^{*}l\bar{\nu}_{l}$ decays, respectively.