Kinetics of a nearly degenerate gas of excitons in Cu/sub 2/O

Summary form only given. The relaxation of a degenerate gas of excitons coupled to an LA-phonon bath toward Bose-Einstein condensation (BEG) is analyzed within the kinetic equations. The optical processes, i.e., the radiative decay and the polariton effect, are included explicitly. The observation of high quantum degeneracy and the asymptotic approach of BEG have been reported for a Bose gas of ortho-x's in Cu/sub 2/O.