Workshop on the Physics of Excited Nucleon – NSTAR2009, Beijing, April 19 – 22, 2009

Invited plenary talk

Invited parallel talk

Oral contribution

Title : The quark model study of multiquark systems

Authors: Jia-Lun Ping

Abstract:

We look for $\Delta\Delta$ and $N\Delta$ dibaryon resonances by calculating NN scattering phase shifts with explicit coupling to these dibaryon channels in Two phenomenological quark models: quark delocalization and color screening model and Salamanca version of chiral quark model. Both models give similar low-energy $NN$ properties and an $IJ^P = 03^+$ $\Delta\Delta$ resonance, which is a promising candidate for the isoscalar ABC structure reported by the CELSIUS-WASA Collaboration. For tetraquark system, a flux-tube quark model with multi-body confinement interaction is employed to study Y(2175) as a tetraquark state. The Y(2175) with diquark-antidiquark structure has energy 2174 MeV which is very consistent with experimental data. The calculation shows that multi-body confinement potential in the multi-quark state should be applied in the quark model.