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Title: Ejecta Masses in Type Ia Supernovae—Implications for the Progenitor and the Explosion Scenario*
Abstract The progenitor system(s) as well as the explosion mechanism(s) of thermonuclear (Type Ia) supernovae are long-standing issues in astrophysics. Here we present ejecta masses and other physical parameters for 28 recent Type Ia supernovae inferred from multiband photometric and optical spectroscopic data. Our results confirm that the majority of SNe Ia showobservableejecta masses below the Chandrasekhar-limit (having a meanMej≈ 1.1 ± 0.3M⊙), consistent with the predictions of recent sub-MChexplosion models. They are compatible with models assuming either single- or double-degenerate progenitor configurations. We also recover a sub-sample of supernovae within 1.2M⊙<Mej< 1.5M⊙that are consistent with near-Chandrasekhar explosions. Taking into account the uncertainties of the inferred ejecta masses, about half of our SNe are compatible with both explosion models. We compare our results with those in previous studies, and discuss the caveats and concerns regarding the applied methodology.  more » « less
Award ID(s):
1911225 1813825 1911151
PAR ID:
10542355
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more » ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; « less
Publisher / Repository:
PASP
Date Published:
Journal Name:
Publications of the Astronomical Society of the Pacific
Volume:
136
Issue:
9
ISSN:
0004-6280
Page Range / eLocation ID:
094201
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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