Type IA supernovae as standard candles

Abstract

view Abstract Citations (77) References (27) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Type IA Supernovae as Standard Candles Branch, David ; Miller, Douglas L. Abstract The distribution of absolute blue magnitudes among Type Ia supernovae (SNs Ia) is studied using supernovae whose apparent magnitudes at maximum light have been well determined and whose parent galaxies have had their relative distances determined by the Tully-Fisher or D_n_ - σ techniques. Most supernovae in the sample appear to have been normal SNs Ia that were essentially unextinguished by dust. These supernovae have a mean absolute blue magnitude M_B_ = -19.72+/-0.06 + 5 log (H_0_/50), with an observational dispersion about the mean of only σ(M_B_) = 0.36, which is comparable to the expected combined errors in distance, apparent magnitude, and extinction. The mean (B - V) color at maximum light is 0.03 +/- 0.04, with a dispersion σ(B - V) = 0.20, which may be due primarily to observational error. The Cepheid-based distance to IC 4182 (Sandage et al. 1992), the parent galaxy of the normal and unextinguished Type Ia SN 1937C, leads to a Hubble constant of H_0_ = 51+/-12 km s^-1^ Mpc^-1^. The sample also includes a few SNs Ia that appear to have been intrinsically normal but reddened and dimmed by dust in their parent galaxies (e.g., SN 1989B), and several having peculiar spectra or light curves which tend to be intrinsically subluminous and red (e.g., SN 199 Ibg). Considering the strong observational selection against subluminous supernovae, and the fact that even when they are discovered they are betrayed by their spectroscopic or photometric peculiarities, their existence does not seriously compromise the use of SNs Ia as distance indicators. Publication: The Astrophysical Journal Pub Date: March 1993 DOI: 10.1086/186752 Bibcode: 1993ApJ...405L...5B Keywords: Blue Stars; Distance; Interstellar Extinction; Standards; Stellar Magnitude; Supernovae; Dispersion; Hubble Constant; Stellar Color; Stellar Spectra; Astrophysics; COSMOLOGY: DISTANCE SCALE; STARS: SUPERNOVAE: GENERAL full text sources ADS | data products SIMBAD (80) NED (80)