{
  "id": "1711.01275",
  "version": "v1",
  "published": "2017-11-03T18:00:06.000Z",
  "updated": "2017-11-03T18:00:06.000Z",
  "title": "Observations of SN 2015F suggest a correlation between the intrinsic luminosity of Type Ia supernovae and the shape of their light curves >900 days after explosion",
  "authors": [
    "Or Graur",
    "David R. Zurek",
    "Armin Rest",
    "Ivo R. Seitenzahl",
    "Benjamin J. Shappee",
    "Robert Fisher",
    "James Guillochon",
    "Michael M. Shara",
    "Adam G. Riess"
  ],
  "comment": "13 pages, 6 figures, 3 tables. Comments welcome",
  "categories": [
    "astro-ph.HE",
    "astro-ph.CO"
  ],
  "abstract": "The late-time light curves of Type Ia supernovae (SNe Ia), observed $>900$ days after explosion, present the possibility of a new diagnostic for SN Ia progenitor and explosion models. First, however, we must discover what physical process (or combination of processes) leads to the slow-down of the late-time light curve relative to a pure $^{56}$Co decay, as observed in SNe 2011fe, 2012cg, and 2014J. We present Hubble Space Telescope observations of SN 2015F, taken $\\approx 600-920$ days past maximum light. Unlike those of the three other SNe Ia, the light curve of SN 2015F remains consistent with being powered solely by the radioactive decay of $^{56}$Co. We fit the light curves of these four SNe Ia in a consistent manner and measure possible correlations between the light curve stretch - a proxy for the intrinsic luminosity of the SN - and the parameters of the physical model used in the fit (e.g., the mass ratio of $^{56}$Co and $^{57}$Co produced in the explosion, or the time at which freeze-out sets in). We propose a new, late-time Phillips-like correlation between the stretch of the SNe and the shape of their late-time light curves, which we parametrize as the difference between their pseudo-bolometric luminosities at 600 and 900 days: $\\Delta L_{900} = {\\rm log}(L_{600}/L_{900})$. This model-independent correlation provides a new way to test which physical process lies behind the slow-down of SN Ia light curves $>900$ days after explosion, and, ultimately, fresh constraints on the various SN Ia progenitor and explosion models.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2017-11-03T18:00:06.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "type ia supernovae",
      "sn 2015f",
      "intrinsic luminosity",
      "late-time light curve",
      "correlation"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 13,
      "language": "en",
      "license": "arXiv",
      "status": "editable"
    }
  }
}