Dmesons at finite temperature and density in the Polyakov–Nambu–Jona-Lasinio model

Abstract

We study D-meson resonances in hot, dense quark matter within the NJL model and its Polyakovloop extension. We show that the mass splitting between D + and D − mesons is moderate, not in excess of 100 MeV. When the decay channel into quasifree quarks opens (Mott effect) at densities above twice saturation density, the decay width reaches rapidly the value of 200 MeV which entails a spectral broadening sufficient to open J/ψ dissociation processes. Contrary to results from hadronic mean-field theories, the chiral quark model does not support the scenario of a dropping D-meson masses so that scenarios for J/ψ dissociation by quark rearrangement built on the lowering of the threshold for this process in a hot and dense medium have to be reconsidered and should account for the spectral broadening.

Correlations between light and heavy flavors near the chiral crossover

“…There exist a number of works on the charmed mesons in nuclear matter, in the context of QCD sum rules [14,[23][24][25] and effective theories [16,[26][27][28][29][30][31][32]. In utilizing our effective theory, a central task is to introduce a reliable density dependence of the interaction parameters, which requires a more microscopic prescription [33].…”

Charmed mesons at finite temperature and chemical potential

“…[12] to finite T and µ; the situation is more complicated than in the vacuum because Lorentz covariance is broken at finite T and µ and special care must be exercised to separate purely divergent contributions from thermal effects, which are finite and do not need regularization. After setting up the scheme, we calculate the masses of the pseudoscalar mesons π + , K 0 and D + at finite T and µ and compare results with those obtained recently using QCD sum rules [18] and those obtained earlier with the NJL model [19,20]. …”

Effect of in-medium spectral density of D and mesons on the dissociation in hadronic matter

“…In this connection the inelastic reaction rates of J/ψ in the hadronic phase have been studied using different effective hadronic models [21,22,23]. In addition, several theoretical efforts [24,25,26,27,28,29,30,31,32,33,34,35,36,37] have been made in order to understand the in-medium behavior of charmed mesons using different hadronic models e.g. QCD sum rules [25,26,27], Quark-Meson Coupling (QMC) [28], Nambu-Jona-Lasinio (NJL) model [29,30].…”

“…In addition, several theoretical efforts [24,25,26,27,28,29,30,31,32,33,34,35,36,37] have been made in order to understand the in-medium behavior of charmed mesons using different hadronic models e.g. QCD sum rules [25,26,27], Quark-Meson Coupling (QMC) [28], Nambu-Jona-Lasinio (NJL) model [29,30]. Most of them have predicted a larger mass drop of open-charm mesons than that of J/ψ which may help to explain the J/ψ suppression in a hadronic environment [24,25,32] although a width enhancement with negligible mass shift of open charm mesons [31,30,34] have also been suggested in order to explain the suppression [30,34].…”