A1 Refereed original research article in a scientific journal
Hydrogen-rich supernovae beyond the neutrino-driven core-collapse paradigm
Authors: Terreran G, Pumo ML, Chen TW, Moriya TJ, Taddia F, Dessart L, Zampieri L, Smartt SJ, Benetti S, Inserra C, Cappellaro E, Nicholl M, Fraser M, Wyrzykowski L, Udalski A, Howell DA, McCully C, Valenti S, Dimitriadis G, Maguire K, Sullivan M, Smith KW, Yaron O, Young DR, Anderson JP, Della Valle M, Elias-Rosa N, Gal-Yam A, Jerkstrand A, Kankare E, Pastorello A, Sollerman J, Turatto M, Kostrzewa-Rutkowska Z, Kozlowski S, Mroz P, Pawlak M, Pietrukowicz P, Poleski R, Skowron D, Skowron J, Soszynski I, Szymanski MK, Ulaczyk K
Publisher: NATURE PUBLISHING GROUP
Publication year: 2017
Journal: Nature Astronomy
Journal name in source: NATURE ASTRONOMY
Journal acronym: NAT ASTRON
Volume: 1
Issue: 10
First page : 713
Last page: 720
Number of pages: 8
ISSN: 2397-3366
DOI: https://doi.org/10.1038/s41550-017-0228-8
Type II supernovae are the final stage of massive stars (above 8 M-circle dot) which retain part of their hydrogen-rich envelope at the moment of explosion. They typically eject up to 15 M-circle dot of material, with peak magnitudes of -17.5 mag and energies in the order of 10(51) erg, which can be explained by neutrino-driven explosions and neutron star formation. Here, we present our study of OGLE-2014-SN-073, one of the brightest type II supernovae ever discovered, with an unusually broad lightcurve combined with high ejecta velocities. From our hydrodynamical modelling, we infer a remarkable ejecta mass of 60(-16)(+42) M-circle dot and a relatively high explosion energy of 12.4(-5.9)(+13.0) x 10(51) erg. We show that this object belongs, along with a very small number of other hydrogen-rich supernovae, to an energy regime that is not explained by standard core-collapse neutrino-driven explosions. We compare the quantities inferred by the hydrodynamical modelling with the expectations of various exploding scenarios and attempt to explain the high energy and luminosity released. We find some qualitative similarities with pair-instability supernovae, although the prompt injection of energy by a magnetar seems to be a viable alternative explanation for such an extreme event.
