{
  "id": "2009.09039",
  "version": "v1",
  "published": "2020-09-18T19:37:04.000Z",
  "updated": "2020-09-18T19:37:04.000Z",
  "title": "A survey of active galaxies at TeV photon energies with the HAWC gamma-ray observatory",
  "authors": [
    "A. Albert",
    "C. Alvarez",
    "J. R. Angeles Camacho",
    "J. C. Arteaga-Velázquez",
    "K. P. Arunbabu",
    "D. Avila Rojas",
    "H. A. Ayala Solares",
    "V. Baghmanyan",
    "E. Belmont-Moreno",
    "S. Y. BenZvi",
    "C. Brisbois",
    "K. S. Caballero-Mora",
    "T. Capistrán",
    "A. Carramiñana",
    "S. Casanova",
    "U. Cotti",
    "J. Cotzomi",
    "S. Coutiño de León",
    "E. De la Fuente",
    "B. L. Dingus",
    "M. A. DuVernois",
    "M. Durocher",
    "J. C. Díaz-Vélez",
    "K. Engel",
    "C. Espinoza",
    "K. L. Fan",
    "M. Fernández Alonso",
    "H. Fleischhack",
    "N. Fraija",
    "A. Galván-Gámez",
    "D. García",
    "J. A. García-González",
    "F. Garfias",
    "M. M. González",
    "J. A. Goodman",
    "J. P. Harding",
    "S. Hernández",
    "B. Hona",
    "D. Huang",
    "F. Hueyotl-Zahuantitla",
    "P. Hüntemeyer",
    "A. Iriarte",
    "A. Jardin-Blicq",
    "V. Joshi",
    "D. Kieda",
    "A. Lara",
    "W. H. Lee",
    "H. León Vargas",
    "J. T. Linnemann",
    "A. L. Longinotti",
    "G. Luis-Raya",
    "J. Lundeen",
    "K. Malone",
    "O. Martínez",
    "I. Martinez-Castellanos",
    "J. Martínez-Castro",
    "J. A. Matthews",
    "P. Miranda-Romagnoli",
    "J. A. Morales-Soto",
    "E. Moreno",
    "M. Mostafá",
    "A. Nayerhoda",
    "L. Nellen",
    "M. Newbold",
    "M. U. Nisa",
    "R. Noriega-Papaqui",
    "L. Olivera-Nieto",
    "A. Peisker",
    "E. G. Pérez-Pérez",
    "C. D. Rho",
    "D. Rosa-González",
    "E. Ruiz-Velasco",
    "H. Salazar",
    "F. Salesa Greus",
    "A. Sandoval",
    "M. Schneider",
    "H. Schoorlemmer",
    "A. J. Smith",
    "R. W. Springer",
    "K. Tollefson",
    "I. Torres",
    "R. Torres-Escobedo",
    "F. Ureña-Mena",
    "L. Villaseñor",
    "T. Weisgarber",
    "E. Willox",
    "A. Zepeda",
    "H. Zhou",
    "C. de León"
  ],
  "comment": "The HAWC survey of Fermi 3FHL AGNs: 30 pages, 13 figures. Submitted to the Astrophysical Journal",
  "categories": [
    "astro-ph.HE"
  ],
  "abstract": "The High Altitude Water Cherenkov Gamma-Ray Observatory (HAWC) continuously detects TeV photons and particles within its large field-of-view, accumulating every day a deeper exposure of two thirds of the sky. We analyzed 1523~days of HAWC live data acquired over four and a half years, in a follow-up analysis of {138} nearby ($z<0.3$) active galactic nuclei from the {\\em Fermi} 3FHL catalog culminating within $40^\\circ$ of the zenith at Sierra Negra, the HAWC site. This search for persistent TeV emission used a maximum-likelihood analysis assuming intrinsic power-law spectra attenuated by pair production of gamma-ray photons with the extragalactic background light. HAWC clearly detects persistent emission from Mkn~421 and Mkn~501, the two brightest blazars in the TeV sky, at 65$\\sigma$ and 17$\\sigma$ level, respectively. {Weaker evidence for long-term emission is found for three other known very-high energy emitters:} the radiogalaxy M87 and the BL Lac objects VER~J0521+211 and 1ES~1215+303, the later two at $z\\sim 0.1$. We find evidence for collective emission from the set of 30 previously reported very high-energy sources that excludes Mkn~421 and Mkn~501 with a random probability $\\sim 10^{-5}$. Upper limits are presented for the sample under the power-law assumption and in the predefined (0.5-2.0), (2.0-8.0) and (8.0-32.0) TeV energy intervals.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2020-09-18T19:37:04.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "hawc gamma-ray observatory",
      "tev photon energies",
      "altitude water cherenkov gamma-ray",
      "water cherenkov gamma-ray observatory",
      "clearly detects persistent emission"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 30,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}