Phenomenological prediction of the properties of the B_{C} system

Abstract

We present a comprehensive calculation of the energies, splittings and electromagnetic decay rates of the bottom charmed meson system. Our calculated result for the ground state lifetime is 0.38 \pm 0.03 ps, in good agreement with the recent CDF measurement. In order to incorporate running coupling constant effects, we choose Richardson's potential for the central potential and take the spin-dependent potentials from the radiative one-loop expressions of Pantaleone, Tye and Ng. The effects of a nonperturbative spin-orbit potential are also included. Our parameters are determined from the low-lying levels of the upsilon system (avg. dev. of 4.3 MeV) and charmonium (avg. dev. of 19.9 MeV). We carry out detailed comparison with the earlier work of Eichten and Quigg and lattice calculations. Our predicted result for the ground state energy is 6286_{-6}^{+15} MeV. Our results are generally in agreement with the earlier calculations. However, we find the two lowest 1^{+} states to be very close to the j-j limit, in agreement with the NRQCD lattice calculations, but at odds with many of the earlier phenomenological calculations. The implications of this finding for the photon spectra of the 1P and 2S states are discussed in some detail. Some strategies for the observation of these states are discussed, and a table of their cascades to the ground state are presented.

Comments: 14 pages Revtex plus 4 postscript figures, now includes calculation of ground state decay rate and justification for use of perturbation theory with contact potentials