{
  "id": "2009.09059",
  "version": "v1",
  "published": "2020-09-18T20:43:49.000Z",
  "updated": "2020-09-18T20:43:49.000Z",
  "title": "Constraints on Axion-like Particles from a Hard $X$-ray Observation of Betelgeuse",
  "authors": [
    "Mengjiao Xiao",
    "Kerstin M. Perez",
    "Maurizio Giannotti",
    "Oscar Straniero",
    "Alessandro Mirizzi",
    "Brian W. Grefenstette",
    "Brandon M. Roach",
    "Melania Nynka"
  ],
  "categories": [
    "astro-ph.HE",
    "hep-ph"
  ],
  "abstract": "We use the first observation of Betelgeuse in hard $X$-rays to perform a novel search for axion-like particles (ALPs). Betelgeuse is not expected to be a standard source of $X$-rays, but light ALPs produced in the stellar core could be converted back into photons in the Galactic magnetic field, producing a detectable flux that peaks in the hard $X$-ray band ($E_\\gamma>10\\mathrm{\\,keV}$). Using a 50 ks observation of Betelgeuse by the $NuSTAR$ satellite telescope, we find no significant excess of events above the expected background. Using models of the regular Galactic magnetic field in the direction of Betelgeuse, we set a 95% C.L. upper limit on the ALP-photon coupling of ${g_{a\\gamma}<(0.5-1.8)\\times10^{-11}}$ GeV$^{-1}$ (depending on magnetic field model) for ALP masses ${m_{a}<(5.5-3.5) \\times10^{-11}}$ eV.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-09-18T20:43:49.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "axion-like particles",
      "betelgeuse",
      "ray observation",
      "regular galactic magnetic field",
      "constraints"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}