Abstract
We investigate the phase structure of QCD at finite temperature and chemical potential by solving a coupled set of truncated Dyson–Schwinger equations for the quark and gluon propagator. In contrast to previous calculations we take into account the full back-reaction of the quarks onto the Yang–Mills sector and we include the effects of strange quarks. We discuss the resulting thermal mass of the unquenched gluon propagator and extract order parameters for the chiral and deconfinement transition from the quarks. Our result for the temperature dependence of the quark condensate at zero chemical potential agrees well with corresponding lattice calculations. We determine the phase diagram at finite chemical potential and find a potential critical endpoint at (μqEP,TEP)≈(190,100) MeV.
Highlights
The existence of a high temperature and/or density phase with quarks and gluons as thermodynamically active degrees of freedom has been a major prediction since the early days of QCD
The quark condensate and dressed Polyakov loop which are shown in Fig. 4 for two light quark flavors at vanishing chemical potential exhibit a crossover behavior around Tc ≈ 200 MeV, with the transition region for chiral symmetry restoration and deconfinement being almost equal
For the gluon we worked with lattice results for the temperature dependence of the electric and magnetic part of the quenched propagator and added quark loop effects determined in the DysonSchwinger equations (DSEs)-framework
Summary
The existence of a high temperature and/or density phase with quarks and gluons as thermodynamically active degrees of freedom has been a major prediction since the early days of QCD. An alternative approach to the QCD phase diagram is functional methods, i.e. the functional renormalization group (FRG) and DysonSchwinger equations (DSEs) These approaches have to rely on approximations in most cases, which are less controlled than those in lattice Monte Carlo simulations. With Dyson-Schwinger equations, lattice data for the quenched gluon where used as an input for the quark DSE to study chiral and deconfinement transitions as well as quark spectral functions in quenched QCD [21, 22]. These calculations were generalized to the two-flavor case and to finite real chemical potential in Ref.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
