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arXiv · 1712.09996

Gauge-invariant screening masses and static quark free energies in $N_f = 2+1$ QCD at non-zero baryon density

Michele Andreoli·Claudio Bonati·Massimo D'Elia·Michele Mesiti·Francesco Negro·Andrea Rucci·Francesco Sanfilippo
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Abstract

We discuss the extension of gauge-invariant electric and magnetic screening masses in the Quark-Gluon Plasma to the case of a finite baryon density, defining them in terms of a matrix of Polyakov loop correlators. We present lattice results for $N_f=2+1$ QCD with physical quark masses, obtained using the imaginary chemical potential approach, which indicate that the screening masses increase as a function of $\mu_B$. A separate analysis is carried out for the theoretically interesting case $\mu_B/T=3 i \pi$, where charge conjugation is not explicitly broken and the usual definition of the screening masses can be used for temperatures below the Roberge-Weiss transition. Finally, we investigate the dependence of the static quark free energy on the baryon chemical potential, showing that it is a decreasing function of $\mu_B$ which displays a peculiar behavior as the pseudocritical transition temperature at $\mu_B=0$ is approached.

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Michele Andreoli, Claudio Bonati, Massimo D'Elia, Michele Mesiti, Francesco Negro, Andrea Rucci, Francesco Sanfilippo. 2017-12-28. Gauge-invariant screening masses and static quark free energies in $N_f = 2+1$ QCD at non-zero baryon density. https://doi.org/10.1103/physrevd.97.054515

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