Signatures of Delayed Detonation, Asymmetry, and Electron Capture in the Mid-Infrared Spectra of Supernovae 2003hv and 2005df

Details Signatures of Delayed Detonation, Asymmetry, and Electron Capture in the Mid-Infrared Spectra of Supernovae 2003hv and 2005df Signatures of Delayed Detonation, Asymmetry, and Electron Capture in the Mid-Infrared Spectra of Supernovae 2003hv and 2005df

2007-02-05

arxiv.org/abs/astro-ph/0702117v1

Astrophys.J.661:995-1012,2007

Astronomy and Astrophysics

Astrophysics

To appear in The Astrophysical Journal

Scientific paper

10.1086/516728

We present the first mid-infrared (5.2-15.2 micron) spectra of Type Ia supernovae (SNe 2003hv and 2005df). The detection of Ni emission in SN 2005df 135 days after the explosion provides direct observational evidence of high-density nuclear burning forming a significant amount of stable Ni in a Type Ia supernova. The observed emission line profiles in the SN 2005df spectrum indicate a chemically stratified ejecta structure. The SN 2005df Ar lines also exhibit a two-pronged emission profile implying that the Ar emission deviates significantly from spherical symmetry. The spectrum of SN 2003hv also shows signs of asymmetry, exhibiting blueshifted [Co III] which matches the blueshift of [Fe II] lines in nearly coeval NIR spectra. Finally, local thermodynamic equilibrium abundance estimates for the yield of radioactive 56Ni give ~0.5 Msun, for SN 2003hv, but only ~0.13-0.22 Msun for the apparently subluminous SN 2005df, supporting the notion that the luminosity of SNe Ia is primarily a function of the radioactive 56Ni yield. The chemically stratified ejecta structure observed in SN 2005df matches the predictions of delayed-detonation (DD) models, but is entirely incompatible with current three-dimensional deflagration models. Furthermore the degree that this layering persists to the innermost regions of the supernova is difficult to explain even in a DD scenario, where the innermost ejecta are still the product of deflagration burning. Thus, while these results are roughly consistent with a delayed detonation, it is clear that a key piece of physics is still missing from our understanding of the earliest phases of SN Ia explosions.

Affiliated with

Also associated with

No associations

Rating

Signatures of Delayed Detonation, Asymmetry, and Electron Capture in the Mid-Infrared Spectra of Supernovae 2003hv and 2005df does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Signatures of Delayed Detonation, Asymmetry, and Electron Capture in the Mid-Infrared Spectra of Supernovae 2003hv and 2005df, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Signatures of Delayed Detonation, Asymmetry, and Electron Capture in the Mid-Infrared Spectra of Supernovae 2003hv and 2005df will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-713817