The bound state corrections to the leptonic decays of the B meson: The light-front approach versus ACM model

A generalization of the parton-like formula is used for the first time to find the differential distributions in the inclusive semileptonic weak decays of the B meson. The main features of this new approach are the treatment of the b quark as an on-mass-shell particle and the inclusion of the effects arising from the b-quark transverse motion in the B meson. Using the b-quark light-front (LF) distribution function related to the equal time momentum wave function taken from the ACM model, we compute the electron energy spectra and the total semileptonic widths of the B meson. We find an impressive agreement between the electron energy spectra calculated in the LF approach and the ones obtained in the ACM model, provided the b-quark mass is identified with the average of the floating b-quark mass in the ACM model. In spite of the simplicity of the model, we obtain a fairly good description of the CLEO data for | Vcb| 0.042.