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arXiv · 1902.09325

Lattice study of QCD at finite chiral density: topology and confinement

N. Yu. Astrakhantsev·V. V. Braguta·A. Yu. Kotov·D. D. Kuznedelev·A. A. Nikolaev
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Abstract

In this paper we study the properties of QCD at nonzero chiral density $\rho_5$, which is introduced through chiral chemical potential $\mu_5$. The study is performed within lattice simulation of QCD with dynamical rooted staggered fermions. We first check that $\rho_5$ is generated at nonzero $\mu_5$ and in the chiral limit observe $\rho_5 \sim \Lambda_{QCD}^2 \mu_5$. We also test the possible connection between confinement and topological fluctuations. To this end, we measured the topological susceptibility $\chi_{\mbox{\footnotesize top}}$ and string tension $\sigma$ for various values of $\mu_5$. We observed that both string tension and chiral susceptibility grow with $\mu_5$ and there is a strong correlation between these quantities. We thus conclude that the chiral chemical potential enhances topological fluctuations and that these fluctuations can indeed be closely related to the strength of confinement.

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N. Yu. Astrakhantsev, V. V. Braguta, A. Yu. Kotov, D. D. Kuznedelev, A. A. Nikolaev. 2019-02-25. Lattice study of QCD at finite chiral density: topology and confinement. https://arxiv.org/abs/1902.09325

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