Density-dependence of the bag constant and nucleon radius in a quark-meson coupling model





Centre d’Etudes Nucléaires de Bordeaux-Gradignan

Université Bordeaux I, IN2P3

rue du Solarium, 33175 Gradignan Cedex, France





The density dependence of the bag constant has been determined self-consistently, in the framework of the quark-meson coupling model, in order to reproduce the basic properties of nuclear matter as well as some physical observables. More precisely, for this calculation, a saturation curve of nuclear matter has been built in such a manner the empirical saturation point and compressibility are reproduced. In addition, the real part of the Schrödinger-equivalent nucleon-nucleus optical potential at saturation density has been constrained to a realistic value and it has been required that the variation of the average nucleon radius in nuclei be compatible with experiment for electron scattering from nuclei. Our results have shown a rather weak increase of the nucleon radius with the density as long as the density is lower than the saturation one in contrast to the results of the usual quark-meson coupling model.