Artículos de revistas
SN 2015bn: a detailed multi-wavelength view of a nearbysuperluminous supernova
Fecha
2016Registro en:
The Astrophysical Journal, 826:39 (31pp), 2016 July 20
10.3847/0004-637X/826/1/39
Autor
Nicholl, M.
Berger, E.
Smartt, S. J.
Margutti, R.
Kamble, A.
Alexander, K. D.
Chen, T. W.
Inserra, C.
Arcavi, I.
Blanchard, P. K.
Cartier Ugarte, Regis
Chambers, K. C.
Childress, M. J.
Chornock, R.
Cowperthwaite, P. S.
Drout, M.
Flewelling, H. A.
Fraser, M.
Gal Yam, Avishay
Galbany, Lluis
Harmanen, J.
Holohien, T- W. -S
Hosseinzadeh, G.
Howell, D. A.
Huber, M. E.
Jerkstrand, A.
Kankare, E.
Kochanek, C. S. C. S.
Lin, Z. -Y.
Lunnan, R.
Magnier, E. A.
Maguire, K.
McCully, C.
McDonald, M.
Metzger, B. D.
Milisavljevic, D.
Mitra, A.
Reynolds, T.
Saario, J.
Shappee, B. J.
Smith, K. W.
Valenti, S.
Villar, V. A.
Waters, C.
Young, D. R.
Institución
Resumen
We present observations of SN 2015bn (=PS15ae = CSS141223-113342+004332 = MLS150211-113342+004333), a Type I superluminous supernova (SLSN) at redshift z = 0.1136. As well as being one of the closest SLSNe I yet discovered, it is intrinsically brighter (M-U approximate to -23.1) and in a fainter galaxy (M-B approximate to -16.0) than other SLSNe at z similar to 0.1. We used this opportunity to collect the most extensive data set for any SLSN I to date, including densely sampled spectroscopy and photometry, from the UV to the NIR, spanning -50 to +250 days from optical maximum. SN 2015bn fades slowly, but exhibits surprising undulations in the light curve on a timescale of 30-50 days, especially in the UV. The spectrum shows extraordinarily slow evolution except for a rapid transformation between +7 and +20-30 days. No narrow emission lines from slow-moving material are observed at any phase. We derive physical properties including the bolometric luminosity, and find slow velocity evolution and non-monotonic temperature and radial evolution. A deep radio limit rules out a healthy off-axis gamma-ray burst, and places constraints on the pre-explosion mass loss. The data can be consistently explained by a greater than or similar to 10 M-circle dot stripped progenitor exploding with similar to 10(51) erg kinetic energy, forming a magnetar with a spin-down timescale of similar to 20 days (thus avoiding a gamma-ray burst) that reheats the ejecta and drives ionization fronts. The most likely alternative scenario-interaction with similar to 20 M-circle dot of dense, inhomogeneous circumstellar material-can be tested with continuing radio follow-up.