{
  "id": "1207.2811",
  "version": "v1",
  "published": "2012-07-11T23:22:51.000Z",
  "updated": "2012-07-11T23:22:51.000Z",
  "title": "The Red Supergiant Progenitor of Supernova 2012aw (PTF12bvh) in Messier 95",
  "authors": [
    "Schuyler D. Van Dyk",
    "S. Bradley Cenko",
    "Dovi Poznanski",
    "Iair Arcavi",
    "Avishay Gal-Yam",
    "Alexei V. Filippenko",
    "Kathryn Silverio",
    "Alan Stockton",
    "Jean-Charles Cuillandre",
    "Geoffrey W. Marcy",
    "Andrew W. Howard",
    "Howard Isaacson"
  ],
  "comment": "14 pages, 6 figures, to appear in ApJ",
  "categories": [
    "astro-ph.SR",
    "astro-ph.CO"
  ],
  "abstract": "We report on the direct detection and characterization of the probable red supergiant progenitor of the intermediate-luminosity Type II-Plateau (II-P) supernova (SN) 2012aw in the nearby (10.0 Mpc) spiral galaxy Messier 95 (M95; NGC 3351). We have identified the star in both Hubble Space Telescope images of the host galaxy, obtained 17-18 yr prior to the explosion, and near-infrared ground-based images, obtained 6-12 yr prior to the SN. The luminous supergiant showed evidence for substantial circumstellar dust, manifested as excess line-of-sight extinction. The effective total-to-selective ratio of extinction to the star was R'_V \\approx 4.35, which is significantly different from that of diffuse interstellar dust (i.e., R_V=3.1), and the total extinction to the star was therefore, on average, A_V \\approx 3.1 mag. We find that the observed spectral energy distribution for the progenitor star is consistent with an effective temperature of 3600 K (spectral type M3), and that the star therefore had a bolometric magnitude of -8.29. Through comparison with recent theoretical massive-star evolutionary tracks we can infer that the red supergiant progenitor had an initial mass 15 \\lesssim M_{ini} (M_sun) < 20. Interpolating by eye between the available tracks, we surmise that the star had initial mass ~17-18 M_sun. The circumstellar dust around the progenitor must have been destroyed in the explosion, as the visual extinction to the SN is found to be low (A_V=0.24 mag with R_V=3.1).",
  "revisions": [
    {
      "version": "v1",
      "updated": "2012-07-11T23:22:51.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "red supergiant progenitor",
      "supernova 2012aw",
      "yr prior",
      "extinction",
      "initial mass"
    ],
    "tags": [
      "journal article"
    ],
    "publication": {
      "doi": "10.1088/0004-637X/756/2/131",
      "journal": "The Astrophysical Journal",
      "year": 2012,
      "month": "Sep",
      "volume": 756,
      "number": 2,
      "pages": 131
    },
    "note": {
      "typesetting": "TeX",
      "pages": 14,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 1122133,
      "adsabs": "2012ApJ...756..131V"
    }
  }
}