English

The diffusion coefficient in the Large Magellanic Cloud

Astrophysics of Galaxies 2025-12-18 v1 High Energy Astrophysical Phenomena

Abstract

The Large Magellanic Cloud (LMC) is the largest satellite galaxy of the Milky Way and provides a unique laboratory for high-energy astrophysics and dark matter studies. In this work, we develop an end-to-end numerical description of cosmic-ray transport and the associated non-thermal emission in the LMC, extending the public DRAGON and HERMES codes. Within this framework, we compute the diffuse synchrotron radiation produced by cosmic-ray electrons in the LMC and compare our predictions with observed low-frequency radio maps. Because electron diffusion imprints a characteristic morphology on the radio emission, this comparison allows us to infer the effective average diffusion coefficient in the LMC. We find a diffusion coefficient D0 = (3-6) ×1028  cm2  s1\times 10^{28} \; \rm{cm}^2 \; \rm{s}^{-1} at 1 GeV, comparable to but slightly larger than values typically inferred for the Milky Way. More generally, this work provides a scalable tool for interpreting non-thermal signals in nearby galaxies and constraining their cosmic-ray transport properties.

Keywords

Cite

@article{arxiv.2512.14906,
  title  = {The diffusion coefficient in the Large Magellanic Cloud},
  author = {Javier Reynoso-Cordova and Daniele Gaggero and Marco Regis and Marco Taoso},
  journal= {arXiv preprint arXiv:2512.14906},
  year   = {2025}
}

Comments

13 pages, 14 figures

R2 v1 2026-07-01T08:28:13.972Z