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arXiv · 2103.07442

Quark Density in Lattice QC$_2$D at Imaginary and Real Chemical Potential

A. Begun·V. G. Bornyakov·N. V. Gerasimeniuk·V. A. Goy·A. Nakamura·R. N. Rogalyov
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Abstract

We study lattice two-color QCD (QC$_2$D) with two flavors of staggered fermions at imaginary and real quark chemical potential $\mu_q$ and $T>T_c$. We employ various methods of extrapolation of the quark number density from imaginary to real quark chemical potentials $\mu_q$, including series expansions as well as analytic continuation based on phenomenological models, and study their accuracy by comparing the results to the lattice data. Below the Roberge-Weiss temperature, $T T_{RW}$ we show that the analytic continuation to the real values of $\mu_q$ based on trigonometric functions works equally well with the conventional method based on the Taylor expansion in powers of $\mu_q$.

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A. Begun, V. G. Bornyakov, N. V. Gerasimeniuk, V. A. Goy, A. Nakamura, R. N. Rogalyov. 2021-03-12. Quark Density in Lattice QC$_2$D at Imaginary and Real Chemical Potential. https://arxiv.org/abs/2103.07442

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