Instanton Effects on the Exotic Meson (Q2Q2) Spectroscopy

The effects of the effective determinantial interaction on the exotic meson (Q'Q') mass spectra are studied. The effective interaction is related to the Fermion zero mode of the background instanton field and is introduced by 't Hooft. The mass shift due to the effective interaction is obtained by the first order perturbation calculation. Our results are expressed by the ground state quark wave function, inside the hadron. The numerical calcula-tion is carried out by borrowing the quark wave function of the MIT bag model. From our analysis it is found that the study of the pattern of mass shift of Q'Q ' states will offer information on the distributions of instantons inside the hadron. It has been shown that Euclidean 4-dimensional non-Abelian gauge theories have interesting classical solutions, called instantons. v Their quantum effects have been studied by 't Hooft and the effective determinantial interaction of all massless Fermions is proposed. 2 ' Further the quantum multi-instanton (anti-instanton) effec