Bottomonium dissociation in a finite density plasma

Nelson R. F. Braga∗ and Luiz F. Ferreira† Instituto de F́ısica, Universidade Federal do Rio de Janeiro, Caixa Postal 68528, RJ 21941-972 – Brazil Abstract We present a holographic description of the thermal behavior of bb̄ heavy vector mesons inside a plasma at finite temperature and density. The meson dissociation in the medium is represented by the decrease in the height of the spectral function peaks. In order to find a description for the evolution of the quasi-states with temperature and chemical potential it is crucial to use a model that is consistent with the decay constant behavior. The reason is that the height of a spectral function peak is related to the value of the zero temperature decay constant of the corresponding particle. AdS/QCD holographic models are in general not consistent with the observation that decay constants of heavy vector mesons decrease with radial excitation level. However, it was recently shown that using a soft wall background and calculating the correlation functions at a finite position of anti-de Sitter space, associated with an ultraviolet energy scale, it is possible to describe the observed behavior. Here we extend this proposal to the case of finite temperature T and chemical potential μ. A clear picture of the dissociation of bottomonium states as a function of μ and T emerges from the spectral function. The energy scales where the change in chemical potential leads to changes in the thermal properties of the mesons is consistent with QCD expectations.