Calculation of hyperfine splitting in mesons using configuration interaction approach

Abstract

The spin-spin mass splitting of light, heavy and mixed mesons are described within a good accuracy in the potential model with screened potential. We conclude that the long-range part of the potential cannot be pure scalar and that a vector-scalar mixture is favored. Exellent spin-spin splittings of heavy quarkonia are obtained with the same parameters as the ones which give the correct average mass spectrum. The results are obtained by going beyond the usually used perturbation method, namely, using a configuration interaction approach.