TY - JOUR
T1 - The nebular spectrum of the Type Ia supernova 2003hv
T2 - evidence for a non-standard event
AU - Mazzali...[et al.], P.A.
AU - Maurer, J.
AU - Stritzinger, Maximilian David
AU - Taubenberger, S.
PY - 2011/9/1
Y1 - 2011/9/1
N2 - 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 ~1 year after the explosion, although the optical spectrum of SN2003hv is reproduced reasonably well for a supernova of luminosity intermediate between normal and subluminous (SN1991bg-like) ones. A possible solution is that the inner layers of the supernova ejecta (v≲ 8000kms-1) contain less mass than predicted by classical explosion models like W7. If this inner region contains ~ 0.5 M⊙ of material, as opposed to ~ 0.9 M⊙ in Chandrasekhar-mass models developed within the single-degenerate scenario, the low density inhibits recombination, favouring the large Feiii/Feii ratio observed in the optical, and decreases the flux in the [Feii] 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.
AB - 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 ~1 year after the explosion, although the optical spectrum of SN2003hv is reproduced reasonably well for a supernova of luminosity intermediate between normal and subluminous (SN1991bg-like) ones. A possible solution is that the inner layers of the supernova ejecta (v≲ 8000kms-1) contain less mass than predicted by classical explosion models like W7. If this inner region contains ~ 0.5 M⊙ of material, as opposed to ~ 0.9 M⊙ in Chandrasekhar-mass models developed within the single-degenerate scenario, the low density inhibits recombination, favouring the large Feiii/Feii ratio observed in the optical, and decreases the flux in the [Feii] 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.
U2 - 10.1111/j.1365-2966.2011.19000.x
DO - 10.1111/j.1365-2966.2011.19000.x
M3 - Journal article
SN - 0035-8711
VL - 416
SP - 881
EP - 892
JO - Royal Astronomical Society. Monthly Notices
JF - Royal Astronomical Society. Monthly Notices
IS - 2
ER -