$B_c$ spectroscopy

Abstract

In the framework of potential models for heavy quarkonium the mass spectrum for the system ($\bar{b}c$) is considered. Spin-dependent splittings, taking into account a change of a constant for effective Coulomb interaction between the quarks, and widths of radiative transitions between the ($\bar{b}c$) levels are calculated. In the framework of QCD sum rules, masses of the lightest vector $B_c^{\ast }$ and pseudoscalar $B_c$ states are estimated, scaling relation for leptonic constants of heavy quarkonia is derived, and the leptonic constant $f_{B_C}$ is evaluated.

Comments: IHEP 94-51, LATEX, 39 pages