Quark models for mesons
1 Department of Physics, Nanjing Normal University, Nanjing 210097, P.R. China
2 School of Mathematics and Physics, Chongqing Jiaotong University, Chongqing 400074, P.R. China
3 Department of Physics, Nanjing University, Nanjing 210093, P.R. China
a e-mail: email@example.com
With the advance of experiment, many high excited states of meson are identified. It is found that many of them are difficult to fit into conventional q meson spectra. Various explanations are proposed. One of them is the four-quark states or molecules of two mesons. In the framework of quark model, by taking into account of multi-body interaction, four-quark states are studied. The results show that the scalar mesons: f0(600), f0(980) and Y(2175) can be well described by four-quark states. Furthermore, unquenched quark model, which incorporates the four-quark components in the conventional q states, is constructed for mesons. By readjusting the model parameters, the model can give a good description of mesons. The model is also used to study the newly discovered XYZ particles.
© Owned by the authors, published by EDP Sciences, 2012