Transient Event from a Core-WD Merger

TYPEAstrophysics Seminar
Speaker:Efrat Gadish Sabach
Time:14:30 - 15:30
Location:Lidow 620
Remark:Master's Seminar. Supervisor: Noam Soker
Abstract:I examine the rare evolutionary routes of two massive stars in a binary system with a total mass of 9 M⊙ − 12M⊙. Each star by itself will end up in a white dwarf (WD),
but due to mass transfer the secondary might become massive enough to be considered a progenitor of a core collapse supernova (CCSN). As the post-accretion companion expands to very large radii a common envelope (CE) phase is inevitable. I calculate the stellar evolution of non-rotating stars with solar metallicity from the ZAMS, using the Modules
for Experiments in Stellar Astrophysics (MESA), and examine the evolution of the system during the CE phase. I considered both partial and complete envelope ejection, synchronization due to tidal forces and Darwin instability. I discuss the possible outcomes of the CE evolution and some of the observational consequences. In some cases an intermediate luminosity optical transient (ILOT) event will precede an explosion, either a thermonuclear or a CCSN.