In-Medium Properties of Heavy Quarkonia

Abstract

AbstractWe discuss the in-medium properties of the heavy quarkonium states, specifically, the medium modifications of the masses of the heavy quarkonia and the partial decay widths of charmonium (bottomonium) state to \(D\bar{D}\) (\(B\bar{B}\)). The medium effects considered are due to the density, temperature, isospin asymmetry, strangeness fraction and magnetic field. The partial decay widths of the heavy quarkonium states are studied using a field theoretical model for composite hadrons with quark (and antiquark) constituents, as well as, using a light quark pair model, namely, the \(^3P_0\) model. The in-medium decay widths are computed from the mass modifications of the hidden and open heavy flavour mesons, calculated using a chiral effective model. The density effects are observed to be the dominant medium effects as compared to the effects from the isospin asymmetry, temperature and strangeness fraction of the medium. In the presence of a strong magnetic field, the mixing of the pseudoscalar and the longitudinal component of the vector charmonium states is observed to lead to substantial modifications to the masses of these states, which is observed to lead to an increase in the decay width of \(\psi (3770)\rightarrow D\bar{D}\), dominantly to the neutral \(D\bar{D}\) pair, at large values of the magnetic fields.KeywordsCharmonium and bottomonium statesIn-medium masses and decay widthsChiral effective model