SUPER-CHANDRASEKHAR SNe Ia STRONGLY PREFER METAL-POOR ENVIRONMENTS

Journal Article · Wed Aug 10 04:00:00 EDT 2011 · Astrophysical Journal Letters

DOI:https://doi.org/10.1088/2041-8205/737/1/L24· OSTI ID:21562475

Khan, Rubab; Stanek, K Z; Stoll, R ^[1]

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1. Department of Astronomy, Ohio State University, 140 West 18th Avenue, Columbus, OH 43210 (United States)

We discuss the emerging trend that super-Chandrasekhar Type Ia Supernovae (SCSNe) with progenitor mass estimates significantly exceeding {approx}1.4 M{sub sun} tend to explode in metal-poor environments. While Taubenberger et al. noted that some of the SCSNe host galaxies are relatively metal-poor, we focus quantitatively on their locations in the hosts to point out that in three out of four cases, the SCSNe explosions occurred in the outer edge of the disks of their hosts. It is therefore very likely that their progenitors had far lower metallicities than those implied by the metallicity of their hosts' central regions. In two cases (SN 2003fg and SN 2009dc) the explosion sites were outside {approx}99% of the host's light, and in one case (SN 2006gz) the host's radial metallicity slope indicates that the explosion site is in a metal-poor region. The fourth case (SN 2007if) has the lowest spectroscopically measured SN Ia host metallicity (Childress et al. 2011). It may be possible to explain each of these unusually bright events through some progenitor scenario specific to that case, but a much simpler and straightforward conclusion would be to ascribe the controlling factor to the only physical aspect they have in common-metal-poor environments.

• OSTI ID: 21562475
• Journal Information: Astrophysical Journal Letters, Journal Name: Astrophysical Journal Letters Journal Issue: 1 Vol. 737; ISSN 2041-8205
• Country of Publication: United States
• Language: English

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