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Investigating effects of the electrical conductivity of QCD matter on charge-dependent directed flow

Nicholas J. Benoit1,*, Takahiro Miyoshi1, Chiho Nonaka1,2,3,4,†, and Hiroyuki R. Takahashi5

  • 1Physics Program, Graduate School of Advanced Science and Engineering, Hiroshima University, Higashi-Hiroshima 739-8511, Japan
  • 2Department of Physics, Nagoya University, Nagoya 464-8602, Japan
  • 3Kobayashi Maskawa Institute, Nagoya University, Nagoya 464-8602, Japan
  • 4International Institute for Sustainability with Knotted Chiral Meta Matter, Hiroshima University, Higashi-Hiroshima 739-8511, Japan
  • 5Department of Natural Sciences, Faculty of Arts and Sciences, Komazawa University, Tokyo 154-8525, Japan

  • *Contact author: njbenoit@hiroshima-u.ac.jp
  • †Contact author: nchiho@hiroshima-u.ac.jp
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Phys. Rev. C 112, 024911 – Published 27 August, 2025

DOI: https://doi.org/10.1103/8trh-rd6d

Abstract

Charge-dependent directed flow is an important observable of electromagnetic fields in relativistic heavy-ion collisions. We demonstrate how the difference in charge-dependent directed flows between protons and antiprotons is sensitive to the resistivity, inverse of quark-gluon plasma's electric conductivity, over different collision centralities. Our model numerically solves the (3 + 1)-dimensional relativistic resistive magnetohydrodynamic equations, assuming the electric conductivity to be a scalar. For this work, we focus on symmetric Au + Au collisions at the top Relativistic Heavy-Ion Collider energy of s=200 GeV. We illustrate the time evolution of the electromagnetic fields in our model and connect that to the charge-dependent directed flow results. Our results highlight the importance of modeling quark-gluon plasma's electric conductivity for charge-dependent observables in relativistic heavy-ion collisions.

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Outline

Information

Phys. Rev. C 112, 024911– Published 27 August, 2025
  • Received 10 February 2025
  • Revised 30 May 2025
  • Accepted 14 July 2025
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