{
  "id": "astro-ph/0008057",
  "version": "v1",
  "published": "2000-08-03T05:18:24.000Z",
  "updated": "2000-08-03T05:18:24.000Z",
  "title": "Evidence from Type Ia Supernovae for an Accelerating Universe",
  "authors": [
    "A. V. Filippenko",
    "A. G. Riess"
  ],
  "comment": "20 pages, 11 included figures, aipproc style file included, to appear in Second Tropical Workshop on Particle Physics and Cosmology: Neutrino and Flavor Physics, ed. J. F. Nieves (New York: American Institute of Physics)",
  "doi": "10.1063/1.1328887",
  "categories": [
    "astro-ph"
  ],
  "abstract": "We review the use of Type Ia supernovae for cosmological distance determinations. Low-redshift SNe Ia (z < 0.1) demonstrate that the Hubble expansion is linear, that H_0 = 65 +/- 2 (statistical) km/s/Mpc, and that the properties of dust in other galaxies are similar to those of dust in the Milky Way. We find that the light curves of high-redshift (z = 0.3-1) SNe Ia are stretched in a manner consistent with the expansion of space; similarly, their spectra exhibit slower temporal evolution (by a factor of 1 + z) than those of nearby SNe Ia. The luminosity distances of our first set of 16 high-redshift SNe Ia are, on average, 10-15% farther than expected in a low mass-density (Omega_M=0.2) universe without a cosmological constant. Preliminary analysis of our second set of 9 SNe Ia is consistent with this. Our work supports models with positive cosmological constant and a current acceleration of the expansion. We address the main potential sources of systematic error; at present, none of them appears to reconcile the data with Omega_Lambda=0 and q_0 >= 0. The dynamical age of the Universe is estimated to be 14.2 +/- 1.7 Gyr, consistent with the ages of globular star clusters.",
  "revisions": [
    {
      "version": "v1",
      "updated": "2000-08-03T05:18:24.000Z"
    }
  ],
  "analyses": {
    "keywords": [
      "type ia supernovae",
      "accelerating universe",
      "low-redshift sne ia",
      "globular star clusters",
      "cosmological distance determinations"
    ],
    "tags": [
      "journal article"
    ],
    "note": {
      "typesetting": "TeX",
      "pages": 20,
      "language": "en",
      "license": "arXiv",
      "status": "editable",
      "inspire": 540691
    }
  }
}