|
| | | | |
| | | |
| Stat |
Members: 3645
Articles: 2'504'585
Articles rated: 2609
24 April 2024 |
|
| | | | |
|
Article overview
| |
|
|
SN 2011ht: Confirming a Class of Interacting Supernovae with Plateau Light Curves (Type IIn-P) | | Jon C. Mauerhan
; Nathan Smith
; Jeffrey M. Silverman
; Alexei V. Filippenko
; Adam N. Morgan
; S. Bradley Cenko
; Mohan Ganeshalingam
; Kelsey I. Clubb
; Thomas Matheson
; | | Date: |
5 Sep 2012 | | Abstract: | We present photometry and spectroscopy of the Type IIn supernova (SN) 2011ht,
identified previously as a SN impostor. The light curve exhibits an abrupt
transition from a well-defined ~120 day plateau to a steep bolometric decline.
Leading up to peak brightness, a hot emission-line spectrum exhibits signs of
interaction with circumstellar material (CSM), in the form of relatively narrow
P-Cygni features of H I and He I superimposed on broad Lorentzian wings. For
the remainder of the plateau phase the spectrum exhibits strengthening P-Cygni
profiles of Fe II, Ca II, and H-alpha. By day 147, after the plateau has ended,
the SN entered the nebular phase, heralded by the appearance of forbidden
transitions of [O I], [O II], and [Ca II] over a weak continuum. At this stage,
the light curve exhibits a low luminosity that is comparable to that
sub-luminous Type II-P supernovae, and a relatively fast visual-wavelength
decline that is significantly steeper than the Co-56 decay rate. However, the
total bolometric decline, including the IR luminosity, is consistent with Co-56
decay, and implies a low Ni-56 mass of ~0.01 M(Sun). We therefore characterize
SN 2011ht as a bona-fide core-collapse SN very similar to the peculiar SNe IIn
1994W and 2009kn. These three SNe define a subclass, which are Type IIn based
on their spectrum, but that also exhibit well-defined plateaus and produce low
Ni-56 yields. We therefore suggest Type IIn-P as a name for this subclass.
Possible progenitors of SNe IIn-P, consistent with the available data, include
8-10 M(Sun) stars, which undergo core collapse as a result of electron capture
after a brief phase of enhanced mass loss; or more massive M>25 M(Sun)
progenitors, which experience substantial fallback of the metal-rich
radioactive ejecta. In either case, the energy radiated by these three SNe
during their plateau must be dominated by CSM interaction (abridged). | | Source: | arXiv, 1209.0821 | | Services: | Forum | Review | PDF | Favorites | |
|
|
No review found.
Did you like this article?
Note: answers to reviews or questions about the article must be posted in the forum section.
Authors are not allowed to review their own article. They can use the forum section.
browser Mozilla/5.0 AppleWebKit/537.36 (KHTML, like Gecko; compatible; ClaudeBot/1.0; +claudebot@anthropic.com)
|
| |
|
|
|
|
News, job offers and information for researchers and scientists:
| |
REGISTER