Tests of the accelerating universe with near-infrared observations of a high-redshift type Ia supernova Academic Article uri icon


  • We have measured the rest-frame B-, V-, and I-band light curves of a high-redshift type Ia supernova (SN Ia), SN 1999Q (z = 0.46), using the Hubble Space Telescope (HST) and ground-based near-infrared detectors. A goal of this study is the measurement of the color excess, EB-I, a sensitive indicator of interstellar or intergalactic dust, which could affect recent cosmological measurements from high-redshift SNe Ia. Our observations disfavor a 30% opacity of SN Ia visual light by dust as an alternative to an accelerating universe. This statement applies to both Galactic-type dust (rejected at the 3.4 σ confidence level) and grayer dust (grain size > 0.1 μm, rejected at the 2.3-2.6 σ confidence level) as proposed by Aguirre. The rest-frame I-band light curve shows the secondary maximum 1 month after the B maximum typical of nearby SNe Ia of normal luminosity, providing no indication of evolution as a function of redshift out to z ≈ 0.5. An expanded set of similar observations could improve the constraints on any contribution of extragalactic dust to the dimming of high-redshift SNe Ia.

author list (cited authors)

  • Riess, A. G., Filippenko, A. V., Liu, M. C., Challis, P., Clocchiatti, A., Diercks, A., ... Oppenheimer, B

complete list of authors

  • Riess, AG||Filippenko, AV||Liu, MC||Challis, P||Clocchiatti, A||Diercks, A||Garnavich, PM||Hogan, CJ||Jha, S||Kirshner, RP||Leibundgut, B||Phillips, MM||Reiss, D||Schmidt, BP||Schommer, RA||Smith, RC||Spyromilio, J||Stubbs, C||Suntzeff, NB||Tonry, J||Woudt, P||Brunner, RJ||Dey, A||Gal, R||Graham, J||Larkin, J||Odewahn, SC||Oppenheimer, B

publication date

  • January 1, 2000 11:11 AM