Finite T Meson Correlations and Quark Deconfinement

Abstract

A simple confining separable interaction Ansatz for the rainbow-ladder truncated QCD Dyson-Schwinger equations is used to implement chiral restoration and quark deconfinement in a study ofqq meson states at finite temperature. The model is fixed at T = 0 by reproducing selected π and ρ properties. Deconfinement and chiral restoration are found to both occur at Tc = 146 MeV. In the pion sector, we investigate Mπ(T ) and fπ(T ) along with the exact QCD mass relation and the GMOR relation. For the vector mode, we investigate the 3-space transverse and longitudinal masses M T ρ (T ) and M L ρ (T ), along with the width for the decay ρ 0 → e + e − . The equation of state (EOS) for the model is investigated in the T − µ plane, a tri-critical point is identified and the relationship to a bag model is discussed. The deconfinement transition in rapidly rotating neutron stars is considered and a new signal from the pulsar timing in binary systems with mass accretion is suggested. The model is used to discuss the possibility of a superconducting quark matter phase.

A Model Study of the Chiral Phase Diagram of QCD

“…These behaviors imply that the chiral phase transition at finite temperature and zero chemical potential is a crossover. Although there are some defects caused by the artefact of the separable model, e.g., the numerical results show that in the range 52 MeV < T < 90 MeV the quark condensate increases as the temperature increases (in fact, it should be monotonously decreasing) and the location of the peak of chiral susceptibility is relatively smaller compared to lattice result [39], this model does give results qualitatively consistent with nowadays prevailing viewpoint [28,29]. Simplicity is a big advantage of this model, it overcomes the difficulty in the summation of the frequency spectrum at finite temperature confronted in many other more sophisticated models [31][32][33] but it can be used to highlight many important underlying mechanisms.…”

“…The rank-2 confining separable model gluon propagator is a generally used effective model in the literature which was first proposed for describing the properties of light flavor pseudoscalar and vector mesons [27,28]. At finite temperature, this model gluon propagator can be written as: …”

“…In fact, these works have been done in [28,29]. But for the readers' convenience, here we would like to calculate some observables, such as the quark condensate and the chiral susceptibility.…”

Chiral quark models with nonlocal separable interactions at finite temperature and chemical potential

“…[13,14], T E ≈ 100 MeV and µ E ≈ 200 − 230 MeV. In this sense, we should remark that the model under consideration predicts a critical temperature at µ = 0 of about 100 MeV [15], somewhat below the values obtained in modern lattice simulations which suggest T c ≈ 140 − 190 MeV [1]. In any case, our calculations seem to indicate that µ E might be smaller than previously expected even in the absence of strangeness degrees of freedom.…”

Chiral Condensate and Mott–Anderson Freeze-Out

“…In addition, it has been demonstrated, that the GMOR relation holds out to the chiral phase transition, where pions merge the continuum of unbound quark matter [36,37]. Furthermore, since the current-quark mass is T − and μ−independent and the pion mass is "chirally protected", the T − and μ−dependence of the chiral condensate should be similar to that of the pion decay constant,…”