Open AccessPeculiar, low‐luminosity Type II supernovae: low‐energy explosions in massive progenitors?
Author(s) -
Zampieri L.,
Pastorello A.,
Turatto M.,
Cappellaro E.,
Benetti S.,
Altavilla G.,
Mazzali P.,
Hamuy M.
Publication year - 2003
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.2003.06082.x
Subject(s) - physics , ejecta , supernova , astrophysics , light curve , pair instability supernova , luminosity , type ii supernova , astronomy , type (biology) , accretion (finance) , stars , galaxy , ecology , biology
A number of supernovae, classified as Type II, show remarkably peculiar properties such as an extremely low expansion velocity and an extraordinarily small amount of 56 Ni in the ejecta. We present a joint analysis of the available observations for two of these peculiar Type II supernovae, SN 1997D and SN 1999br, using a comprehensive semi‐analytic method that can reproduce the light curve and the evolution of the line velocity and continuum temperature. We find that these events are underenergetic with respect to a typical Type II supernova and that the inferred mass of the ejecta is relatively large. We discuss the possibility that these supernovae originate from the explosion of a massive progenitor in which the rate of early infall of stellar material on the collapsed core is large. Events of this type could form a black hole remnant, giving rise to significant fallback and late‐time accretion.