The nebular spectrum of the Type Ia supernova 2003hv: evidence for a non-standard event
2011 (English)In: Monthly notices of the Royal Astronomical Society, ISSN 0035-8711, E-ISSN 1365-2966, Vol. 416, no 2, 881-892 p.Article in journal (Refereed) Published
The optical and near-infrared (near-IR) late-time spectra of the under-luminous Type Ia supernova 2003hv are analysed with a code that computes the nebular emission from a supernova nebula. Synthetic spectra based on the classical explosion model W7 are unable to reproduce the large FeIII/FeII ratio and the low IR flux at similar to 1 year after the explosion, although the optical spectrum of SN 2003hv is reproduced reasonably well for a supernova of luminosity intermediate between normal and subluminous (SN 1991bg-like) ones. A possible solution is that the inner layers of the supernova ejecta (v less than or similar to 8000 km s(-1)) contain less mass than predicted by classical explosion models like W7. If this inner region contains similar to 0.5 M(circle dot) of material, as opposed to similar to 0.9 M(circle dot) in Chandrasekhar-mass models developed within the single-degenerate scenario, the low density inhibits recombination, favouring the large Fe III/Fe II ratio observed in the optical, and decreases the flux in the [Fe II] lines which dominate the IR spectrum. The most likely scenario may be an explosion of a sub-Chandrasekhar-mass white dwarf. Alternatively, the violent/dynamical merger of two white dwarfs with the combined mass exceeding the Chandrasekhar limit also shows a reduced inner density.
Place, publisher, year, edition, pages
2011. Vol. 416, no 2, 881-892 p.
radiation mechanisms: thermal, supernovae: general, supernovae: individual: SN 2003hv
IdentifiersURN: urn:nbn:se:su:diva-67281DOI: 10.1111/j.1365-2966.2011.19000.xISI: 000295119900006OAI: oai:DiVA.org:su-67281DiVA: diva2:470920
authorCount :62011-12-302011-12-272011-12-30Bibliographically approved