SNhunt151: an explosive event inside a dense cocoon
Date Issued
2018
Author(s)
•
•
•
•
Terreran, G.
•
Morales-Garoffolo, A.
•
Howerton, S. C.
•
Valenti, S.
•
Kankare, E.
•
Drake, A. J.
•
Djorgovski, S. G.
•
•
•
Kangas, T.
•
Ochner, P.
•
Filippenko, A. V.
•
Ciabattari, F.
•
Geier, S.
•
Howell, D. A.
•
Isern, J.
•
Leonini, S.
•
Pignata, G.
•
Abstract
SNhunt151 was initially classified as a supernova (SN) impostor (nonterminal outburst of a massive star). It exhibited a slow increase in luminosity, lasting about 450 d, followed by a major brightening that reaches M_V ≈ -18 mag. No source is detected to M_V ≳ -13 mag in archival images at the position of SNhunt151 before the slow rise. Low-to-mid-resolution optical spectra obtained during the pronounced brightening show very little evolution, being dominated at all times by multicomponent Balmer emission lines, a signature of interaction between the material ejected in the new outburst and the pre-existing circumstellar medium. We also analysed mid-infrared images from the Spitzer Space Telescope, detecting a source at the transient position in 2014 and 2015. Overall, SNhunt151 is spectroscopically a Type IIn SN, somewhat similar to SN 2009ip. However, there are also some differences, such as a slow pre-discovery rise, a relatively broad light-curve peak showing a longer rise time (∼50 d), and a slower decline, along with a negligible change in the temperature around the peak (T ≤ 10^4 K). We suggest that SNhunt151 is the result of an outburst, or an SN explosion, within a dense circumstellar nebula, similar to those embedding some luminous blue variables like η Carinae and originating from past mass-loss events.
Volume
475
Issue
2
Start page
2614
Issn Identifier
0035-8711
Ads BibCode
2018MNRAS.475.2614E
Rights
open.access
File(s)![Thumbnail Image]()
![Thumbnail Image]()
Loading...
Name
sty009.pdf
Description
Pdf editoriale
Size
4.55 MB
Format
Adobe PDF
Checksum (MD5)
82a8f8df8ca9b6dec2b41784af4f3241
Loading...
Name
EliasRosa_2018MNRAS.475.2614E_preprint.pdf
Description
preprint
Size
3.23 MB
Format
Adobe PDF
Checksum (MD5)
d6c392ac8a619d2f3909eb786115f66e