Semileptonic $B o D^{(*)}l u$ decays, the slope of Isgur-Wise function and $|V_{bc}|$ value in potential quark model

摘要

The modification of the naive potential model of the heavy meson isconsidered on the basis of the single-time prescription for the quark-mesonform factor and the covariant choice of the quatk relative momentum. Theapplication of the model to the description of the semileptonic decays of thebeauty meson allows one to determine the Isgur-Wise function slope$\rho^2\simeq 1.25$ and to extract the value $|V_{bc}|= 0.038\pm 0.003$ fromthe experimental data.