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arXiv · 2608.21600

Photon production from gluon splitting and fusion induced by a magnetic field of arbitrary strength in relativistic heavy-ion collisions

Alejandro Ayala·Santiago Bernal-Langarica·José Jorge Medina-Serna·Ana Julia Mizher
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Abstract

We compute the yield and elliptic flow coefficient for photons produced during the pre-equilibrium stage of semi-central relativistic heavy-ion collisions from the gluon fusion and splitting processes induced by the presence of a magnetic field. The calculation is performed for arbitrary values of the field strength. The pre-equilibrium gluon distribution is modeled with a glasma-inspired Bose-Einstein occupation factor, as well as with an anisotropic distribution that accounts for the rapid initial expansion along the beam axis. In both cases, we find a very good agreement between the calculation and the experimental data from PHENIX. Most notably, the shape and strength of the elliptic flow coefficient are described quite well, representing a step towards solving the outstanding photon puzzle.

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Alejandro Ayala, Santiago Bernal-Langarica, José Jorge Medina-Serna, Ana Julia Mizher. 2026-08-21. Photon production from gluon splitting and fusion induced by a magnetic field of arbitrary strength in relativistic heavy-ion collisions. https://arxiv.org/abs/2608.21600

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