Property of cn - nbar cbar System in U(12)-Scheme and X(3872),Y(3940)

Abstract

The properties of four quark cn - nbar cbar states are investigated as cn di-quark and nbar cbar di-antiquark system in U(12)-classification scheme of hadrons. We consider the negative-parity di-quark and di-antiquark in ground states, and the properties of X(3872) and Y(3940) are consistent, respectively, with those of the JPC=1++ and 2++ states from these negative-parity di-quark and di-antiquark. Their narrow-widths are explained from an orthogonality of spinor wave functions. The properties of ground-state cs - sbar cbar system are also predicted in this scheme.

Comments: 8pages, proceedings of HADRON'05, CBPF, Rio de Janeiro, August 2005