TY - JOUR
T1 - Massive Stellar Mergers as Precursors of Hydrogen-rich Pulsational Pair Instability Supernovae
AU - Vigna Gomez, Alejandro
AU - Justham, Stephen
AU - Mandel, Ilya
AU - De Mink, Selma E.
AU - Podsiadlowski, Philipp
PY - 2019/5/10
Y1 - 2019/5/10
N2 - Interactions between massive stars in binaries are thought to be responsible for much of the observed diversity of supernovae. As surveys probe rarer populations of events, we should expect to see supernovae arising from increasingly uncommon progenitor channels. Here we examine a scenario in which massive stars merge after they have both formed a hydrogen-exhausted core. We suggest that this could produce stars that explode as pair-instability supernovae (PISNe) with significantly more hydrogen, at a given metallicity, than in single-star models with the same pre-explosion oxygen-rich core mass. We investigate the subset of those stellar mergers that later produce pulsational PISNe, and estimate that the rate of such post-merger, hydrogen-rich pulsational PISNe could approach a few in a thousand of all core-collapse supernovae. The nature and predicted rate of such hydrogen-rich pulsational PISNe are reminiscent of the very unusual supernova iPTF14hls. For plausible assumptions, PISNe from similar mergers might dominate the rate of PISNe in the local Universe.
AB - Interactions between massive stars in binaries are thought to be responsible for much of the observed diversity of supernovae. As surveys probe rarer populations of events, we should expect to see supernovae arising from increasingly uncommon progenitor channels. Here we examine a scenario in which massive stars merge after they have both formed a hydrogen-exhausted core. We suggest that this could produce stars that explode as pair-instability supernovae (PISNe) with significantly more hydrogen, at a given metallicity, than in single-star models with the same pre-explosion oxygen-rich core mass. We investigate the subset of those stellar mergers that later produce pulsational PISNe, and estimate that the rate of such post-merger, hydrogen-rich pulsational PISNe could approach a few in a thousand of all core-collapse supernovae. The nature and predicted rate of such hydrogen-rich pulsational PISNe are reminiscent of the very unusual supernova iPTF14hls. For plausible assumptions, PISNe from similar mergers might dominate the rate of PISNe in the local Universe.
KW - Binaries: General
KW - stars: Massive
KW - supernovae: General
UR - http://www.scopus.com/inward/record.url?scp=85067311197&partnerID=8YFLogxK
U2 - 10.3847/2041-8213/ab1bdf
DO - 10.3847/2041-8213/ab1bdf
M3 - Article
AN - SCOPUS:85067311197
SN - 2041-8205
VL - 876
SP - 1
EP - 6
JO - The Astrophysical Journal Letters
JF - The Astrophysical Journal Letters
IS - 2
M1 - L29
ER -