Research Of Heavy Quarkonium Theory

If the c quark has an anomalous color-electric dipole moment (CEDM), it may serve as a new source of CP violation. The strength of such a CP violation depends on the size of the CEDM, d’c. We propose two effective ways of testing it from the large sample of Ψ′â†'J/Ψ+Ï€++Ï€-at the Beijing Spectrometer, and the obtained result,|dc|3x10-14e cm (95%C.L.), gives the first experimentally determined upper bound on the CEDM of the c quark.For the states near threshold, coupled-channel effect makes important contribution. At the same time, relativistic correction becomes non-negligible. Using two body Dirac equation and3P0quark pair creation model, we build a potential model that include both coupled-channel effect and relativistic correction. By adjust the parameters of the potential, we obtain better spectrum than previous models.