THE RISE TIME OF NORMAL AND SUBLUMINOUS TYPE Ia SUPERNOVAE

Journal Article · Fri Jan 20 00:00:00 EST 2012 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/745/1/44· OSTI ID:22012006

Gonzalez-Gaitan, S; Perrett, K; Carlberg, R ^[1]; Conley, A ^[2]; Bianco, F B; Howell, D A; Graham, M L ^[3]; Sullivan, M; Hook, I M ^[4]; Astier, P; Balland, C; Fourmanoit, N; Guy, J; Hardin, D; Pain, R ^[5]; Balam, D ^[6]; Basa, S ^[7]; Fouchez, D ^[8]; Lidman, C ^[9]; Palanque-Delabrouille, N ^[10] ; others, and

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1. Department of Astronomy and Astrophysics, University of Toronto, 50 St. george Street, Toronto, ON M5S 3H4 (Canada)
2. Center for Astrophysics and Space Astronomy, University of Colorado, 593 UCB, Boulder, CO 80309-0593 (United States)
3. Department of Physics, University of California, Santa Barbara, Broida Hall, Mail Code 9530, Santa Barbara, CA 93106-9530 (United States)
4. Department of Physics (Astrophysics), University of Oxford, DWB, Keble Road, Oxford, OX1 3RH (United Kingdom)
5. LPNHE, Universite Pierre et Marie Curie Paris 6, Universite Paris Diderot Paris 7, CNRS-IN2P3, 4 Place Jussieu, 75252 Paris Cedex 05 (France)
6. Dominion Astrophysical Observatory, Herzberg Institute of Astrophysics, 5071 West Saanich Road, Victoria, BC V9E 2E7 (Canada)
7. Laboratoire d'Astrophysique de Marseille, Pole de l'Etoile Site de Chateau-Gombert, 38, rue Frederic Joliot-Curie, 13388 Marseille cedex 13 (France)
8. CPPM, CNRS-IN2P3 and University Aix Marseille II, Case 907, 13288 Marseille cedex 9 (France)
9. Australian Astronomical Observatory, P.O. Box 296, Epping, NSW 1710 (Australia)
10. DSM/IRFU/SPP, CEA-Saclay, F-91191 Gif-sur-Yvette (France)

We calculate the average stretch-corrected rise time of Type Ia supernovae (SNe Ia) in the Supernova Legacy Survey. We use the aggregate light curves of spectroscopic and photometrically identified SNe Ia to fit the rising part of the light curve with a simple quadratic model. We obtain a light curve shape corrected, i.e., stretch-corrected, fiducial rise time of 17.02{sup +0.18}{sub -0.28} (stat) days. The measured rise time differs from an earlier finding by the SNLS (Conley et al.) due to the use of different SN Ia templates. We compare it to nearby samples using the same methods and find no evolution in the early part of the light curve of SNe Ia up to z = 1. We search for variations among different populations, particularly subluminous objects, by dividing the sample in stretch. Bright and slow decliners (s > 1.0) have consistent stretch-corrected rise times compared to fainter and faster decliners (0.8 < s {<=} 1.0); they are shorter by 0.57{sup +0.47}{sub -0.50} (stat) days. Subluminous SNe Ia (here defined as objects with s {<=} 0.8), although less constrained, are also consistent, with a rise time of 18.03{sup +0.81}{sub -1.37} (stat) days. We study several systematic biases and find that the use of different fiducial templates may affect the average rise time but not the intrinsic differences between populations. Based on our results, we estimate that subluminous SNe Ia are powered by 0.05-0.35 M{sub Sun} of {sup 56}Ni synthesized in the explosion. Our conclusions are the same for the single-stretch and two-stretch parameterizations of the light curve.

• OSTI ID: 22012006
• Journal Information: Astrophysical Journal, Vol. 745, Issue 1; Other Information: Country of input: International Atomic Energy Agency (IAEA); ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTROPHYSICS
COSMOLOGY AND ASTRONOMY
EXPLOSIONS
NICKEL 56
PULSE RISE TIME
STAR EVOLUTION
SUPERNOVAE