Evidence of short-lived SN Ia progenitors

¹ Astroparticule et Cosmologie APC, UMR 7164, Université Paris Diderot, 10 rue Alice Domon et Léonie Duquet, 75205 Paris Cedex 13, France e-mail: aubourg@in2p3.fr
² CEA, Irfu, SPP, Centre de Saclay, 91191 Gif-sur-Yvette Cedex, France
³ Department of Astrophysical Sciences, Peyton Hall, Princeton University, Princeton, NJ 08544, USA
⁴ SUPA, Institute for Astronomy, University of Edinburgh, Royal Observatory, Blackford Hill, Edinburgh EH9-3HJ, UK
⁵ Institute of Space Sciences (CSIC-IEEC)/ICREA, Campus UAB, Barcelona 08193, Spain

Received: 18 March 2008
Accepted: 26 October 2008

Abstract

We use the VESPA algorithm and spectra from the Sloan Digital Sky Survey to investigate the star formation history of the host galaxies of 257 type Ia supernovae. We find 5σ evidence of a short-lived population of progenitors with lifetimes of less than 180 Myr, indicating a type Ia supernova channel arising from stars in the mass range ~3.5-8 . As standardizeable candles, type Ia supernovae play an important role in determining the expansion history of the Universe, but to be useful for future cosmological surveys, the peak luminosity needs to be free of uncorrected systematic effects at the level of 1-2%. If the different progenitor routes lead to supernovae with even moderately small differences in properties, then these need to be corrected for separately, or they could lead to a systematic bias in future supernovae surveys, as the prompt route is likely to increase in importance at high redshift. VESPA analysis of hosts could be a valuable tool in this, by identifying which progenitor route is most likely.