HEAVY QUARKONIUM POTENTIAL MODEL AND THE P-1(1) STATE OF CHARMONIUM

A theoretical explanation of the observed splittings among the P state s of charmonium is given with the use of a nonsingular potential model for heavy quarkonia. We also show that the recently observed mass dif ference between the center of gravity of the P-3(J) states and the P-1 (1) state of <<c(c)over bar> does not provide a direct test of the col or hyperfine interaction in heavy quarkonia. Our theoretical value for the mass of the P-1(1) state is in agreement with the experimental re sult, and its E1 transition width is 341.8 keV. The mass of the eta(c) state is predicted to be 3622.3 Mev.