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  • Open Access

Spacetime profile of electromagnetic fields in intermediate-energy heavy-ion collisions

Hidetoshi Taya*

  • Department of Physics, Keio University, 4-1-1 Hiyoshi, Kanagawa 223-8521, Japan and iTHEMS, TRIP Headquarters, RIKEN, Wako 351-0198, Japan

  • *Contact author: h_taya@keio.jp
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Phys. Rev. C 112, 024904 – Published 18 August, 2025

DOI: https://doi.org/10.1103/t52d-qcw1

Abstract

I numerically estimate the spacetime profile of the electromagnetic fields produced in intermediate-energy heavy-ion collisions at sNN=2.4–7.7GeV for a wide range of impact parameters b=0–9fm, using a hadronic cascade model, jam (Jet AA Microscopic transport model). I demonstrate that (1) the produced electromagnetic fields are as strong as eE,eB=O((50MeV)2); (2) that the produced fields extend in spacetime about V4=O((10fm)4); (3) that the magnetic field dominates around the collision point, while the other broad regions of spacetime are dominated by the electric field; and (4) that a topological electromagnetic-field configuration such that E·B≠0 is realized.

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Phys. Rev. C 112, 024904– Published 18 August, 2025
  • Received 4 February 2025
  • Revised 8 May 2025
  • Accepted 17 June 2025
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI. Funded by SCOAP3.

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