Early Ni-56 decay gamma rays from SN2014J suggest an unusual explosion
2014 (English)In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 345, no 6201, 1162-1165 p.Article in journal (Refereed) Published
Type Ia supernovae result from binary systems that include a carbon-oxygen white dwarf, and these thermonuclear explosions typically produce 0.5 solar mass of radioactive Ni-56. The Ni-56 is commonly believed to be buried deeply in the expanding supernova cloud. In SN2014J, we detected the lines at 158 and 812 kiloelectron volts from Ni-56 decay (time similar to 8.8 days) earlier than the expected several-week time scale, only similar to 20 days after the explosion and with flux levels corresponding to roughly 10% of the total expected amount of Ni-56. Some mechanism must break the spherical symmetry of the supernova and at the same time create a major amount of Ni-56 at the outskirts. A plausible explanation is that a belt of helium from the companion star is accreted by the white dwarf, where this material explodes and then triggers the supernova event.
Place, publisher, year, edition, pages
2014. Vol. 345, no 6201, 1162-1165 p.
IdentifiersURN: urn:nbn:se:su:diva-107787DOI: 10.1126/science.1254738ISI: 000341179800042OAI: oai:DiVA.org:su-107787DiVA: diva2:753028