Chiral Lagrangian Treatment of 0 ++ Mesons and 0 ++ Glueballs

Within the framework of a nonlinear chiral Lagrangian the mass spectra and the decay properties of 0 ++ states below 2 GeV are studied. Assuming that f 0 (980), a 0 (980), K * 0 (1430), and f 0 (1500) comprise an SU (3) nonet, we make a detailed prediction about the static properties of the 0 ++ mesons. The substructure analysis of these states in terms of two- and four-quark components as well as a glueball component is carried out. We also consider the interaction Lagrangian and provide a preliminary study of the strong and radiative decays of the 0 ++ mesons. The scalar glueball masses and partial widths are also presented. In view of the fact that few data of 0 ++ mesons are clearly given in the present PDG (Particle Data Group) list and that the four-quark content of mesons is a hot issue both experimentally and theoretically, the predicted results of the paper may be helpful for upcoming experimental and theoretical studies of these mesons.