A1 Vertaisarvioitu alkuperäisartikkeli tieteellisessä lehdessä
On the triple peaks of SNHunt248 in NGC 5806
Tekijät: Kankare E, Kotak R, Pastorello A, Fraser M, Mattila S, Smartt SJ, Bruce A, Chambers KC, Elias-Rosa N, Flewelling H, Fremling C, Harmanen J, Huber M, Jerkstrand A, Kangas T, Kuncarayakti H, Magee M, Magnier E, Polshaw J, Smith KW, Sollerman J, Tomasella L
Kustantaja: EDP SCIENCES S A
Julkaisuvuosi: 2015
Journal: Astronomy and Astrophysics
Tietokannassa oleva lehden nimi: ASTRONOMY & ASTROPHYSICS
Lehden akronyymi: ASTRON ASTROPHYS
Artikkelin numero: ARTN L4
Vuosikerta: 581
Sivujen määrä: 7
ISSN: 1432-0746
DOI: https://doi.org/10.1051/0004-6361/201526631
We present our findings on a supernova (SN) impostor, SNHunt248, based on optical and near-IR data spanning similar to 15 yr before discovery, to similar to 1 yr post-discovery. The light curve displays three distinct peaks, the brightest of which is at MR similar to -15.0 mag. The post-discovery evolution is consistent with the ejecta from the outburst interacting with two distinct regions of circumstellar material. The 0.5-2.2 mu m spectral energy distribution at -740 d is well-matched by a single 6700 K blackbody with log(L/L-circle dot) similar to 6.1. This temperature and luminosity support previous suggestions of a yellow hypergiant progenitor; however, we find it to be brighter than the brightest and most massive Galactic late-F to early-G spectral type hypergiants. Overall the historical light curve displays variability of up to similar to +/- 1 mag. At current epochs (similar to 1 yr post-outburst), the absolute magnitude (MR similar to -9 mag) is just below the faintest observed historical absolute magnitude similar to 10 yr before discovery.