Heavy quark and chiral symmetry predictions for semileptonic decaysB¯→D(D*)πℓν¯

We study in detail the prediction for the semileptonic decays $\bar{B} \to D (D^*) \pi \ell \bar{\nu}$ by heavy quark and chiral symmetry. The branching ratio for $\bar{B} \to D \pi \ell \bar{\nu}$ is quite significant, as big as $(0.5-1)\%$. The branching ratio for $\bar{B} \to D^* \pi \ell \bar{\nu}$ is only of order $10^{-4}-10^{-5}$. Numerical results for various single particle spectra and their dependence on the pion momentum cutoff schemes are presented in a series of figures, as are the model independent ratios for differential rates of $D$ and $D^*$. We also study the parity-violation effects on the decay rates for different polarization states of the $D^*$. Figures may be obtained by anonymous FTP from strange.tn.cornell.edu in the directory pub/CLNS931204, or by email from the author.Comment: 28 pages, 23 figs (FTP from author), LaTeX, Typos corrected in Eq. 4.9c (factor of 2), Eq. A.4, and Tables II & III. No change in content, results, or figures. CLNS93/1204, IP-ASTP-15-9