{
  "id": "1310.7805",
  "version": "v1",
  "published": "2013-10-29T13:59:53.000Z",
  "updated": "2013-10-29T13:59:53.000Z",
  "title": "Hadronic Gamma-Ray and Neutrino Emission from Cygnus X-3",
  "authors": [
    "N. Sahakyan",
    "G. Piano",
    "M. Tavani"
  ],
  "comment": "Accepted for publication in ApJ",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "Cygnus X-3 (Cyg X-3) is a remarkable Galactic microquasar (X-ray binary) emitting from radio to $\\gamma$-ray energies. In this paper, we consider hadronic model of emission of $\\gamma$-rays above 100 MeV and their implications. We focus here on the joint $\\gamma$-ray and neutrino production resulting from proton-proton interactions within the binary system. We find that the required proton injection kinetic power, necessary to explain the $\\gamma$-ray flux observed by AGILE and Fermi-LAT, is $L_p \\sim 10^{38}\\:\\rm{erg\\:s^{-1}}$, a value in agreement with the average bolometric luminosity of the hypersoft state (when Cygnus X-3 was repeatedly observed to produce transient $\\gamma$-ray activity). If we assume an increase of the wind density at the superior conjunction, the asymmetric production of $\\gamma$-rays along the orbit can reproduce the observed modulation. According to observational constraints and our modelling, a maximal flux of high-energy neutrinos would be produced for an initial proton distribution with a power-law index $\\alpha=2.4$. The predicted neutrino flux is almost two orders of magnitude less than the 2-month IceCube sensitivity at $\\sim$1 TeV. If the protons are accelerated up to PeV energies, the predicted neutrino flux for a prolonged \"soft X-ray state\" would be a factor of about 3 lower than the 1-year IceCube sensitivity at $\\sim$10 TeV. This study shows that, for a prolonged soft state (as observed in 2006) possibly related with $\\gamma$-ray activity and a hard distribution of injected protons, Cygnus X-3 might be close to being detectable by cubic-kilometer neutrino telescopes such as IceCube.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2013-10-29T13:59:53.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "neutrino emission",
      "hadronic gamma-ray",
      "predicted neutrino flux",
      "proton injection kinetic power",
      "ray activity"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/780/1/29",
      "journal": "The Astrophysical Journal",
      "year": 2014,
      "month": "Jan",
      "volume": 780,
      "number": 1,
      "pages": 29
    },
    "note": {
      "typesetting": "TeX",
      "pages": 0,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1262496,
      "adsabs": "2014ApJ...780...29S"
    }
  }
}