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arXiv · 2203.06159

Numerical Study of the Roberge-Weiss Transition

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

We study the Roberge-Weiss phase transition numerically. The phase transition is associated with the discontinuities in the quark-number density at specific values of imaginary quark chemical potential. We parameterize the quark number density $\rho_q$ by the polynomial fit function to compute the canonical partition functions. We demonstrate that this approach provides a good framework for analyzing lattice QCD data at finite density and a high temperature. We show numerically that at high temperature, the Lee-Yang zeros lie on the negative real semi-axis provided that the high-quark-number contributions to the grand canonical partition function are taken into account. These Lee-Yang zeros have nonzero linear density, which signals the Roberge-Weiss phase transition. We demonstrate that this density agrees with the quark density discontinuity at the transition line.

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V. G. Bornyakov, N. V. Gerasimeniuk, V. A. Goy, A. A. Korneev, A. V. Molochkov, A. Nakamura, R. N. Rogalyov. 2022-03-11. Numerical Study of the Roberge-Weiss Transition. https://doi.org/10.1103/physrevd.107.014508

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