Journal Article

Characteristic velocities of stripped-envelope core-collapse supernova cores*

J. I. Maurer, P. A. Mazzali, J. Deng, A. V. Filippenko, M. Hamuy, R. P. Kirshner, T. Matheson, M. Modjaz, E. Pian, M. Stritzinger, S. Taubenberger and S. Valenti

in Monthly Notices of the Royal Astronomical Society

Published on behalf of The Royal Astronomical Society

Volume 402, issue 1, pages 161-172
Published in print February 2010 | ISSN: 0035-8711
Published online February 2010 | e-ISSN: 1365-2966 | DOI: http://dx.doi.org/10.1111/j.1365-2966.2009.15905.x
Characteristic velocities of stripped-envelope core-collapse supernova cores*

More Like This

Show all results sharing this subject:

  • Astronomy and Astrophysics

GO

Show Summary Details

Preview

The velocity of the inner ejecta of stripped-envelope core-collapse supernovae (CC-SNe) is studied by means of an analysis of their nebular spectra. Stripped-envelope CC-SNe are the result of the explosion of bare cores of massive stars (≥8 M), and their late-time spectra are typically dominated by a strong [O i]λλ6300, 6363 emission line produced by the innermost, slow-moving ejecta which are not visible at earlier times as they are located below the photosphere. A characteristic velocity of the inner ejecta is obtained for a sample of 56 stripped-envelope CC-SNe of different spectral types (IIb, Ib, Ic) using direct measurements of the linewidth as well as spectral fitting. For most SNe, this value shows a small scatter around 4500 km s−1. Observations (<100 d) of stripped-envelope CC-SNe have revealed a subclass of very energetic SNe, termed broad-lined SNe (BL-SNe) or hypernovae, which are characterized by broad absorption lines in the early-time spectra, indicative of outer ejecta moving at very high velocity (v≥ 0.1c). SNe identified as BL in the early phase show large variations of core velocities at late phases, with some having much higher and some having similar velocities with respect to regular CC-SNe. This might indicate asphericity of the inner ejecta of BL-SNe, a possibility we investigate using synthetic three-dimensional nebular spectra.

Keywords: line: profiles; radiative transfer; supernovae: general

Journal Article.  9532 words.  Illustrated.

Subjects: Astronomy and Astrophysics

Full text: subscription required

How to subscribe Recommend to my Librarian

Users without a subscription are not able to see the full content. Please, subscribe or login to access all content.