Geosciences Dept. Seminar: Long-Term Evolution of Binaries Toward SNIa

Abstract:

Can a white dwarf (WD) in a semi-detached binary system, accreting mass from its secondary, secularly grow, eventually reaching the Chandrasekhar mass and explode as a Type Ia supernovae (SNIa)? Via simulations of long term evolution over tens of thousands of nova cycles, we have determined the parameter space, defined by the WD mass, central temperature, and accretion rate, that may allow such growth. We have accounted for limits on the secondary mass as well as the time frame.  Furthermore, we have tackled the long lasting reservation regarding the consequences of the accumulation and ejection of a thick helium shell by successfully simulating many hundreds of consecutive helium flashes and hence unveiled the manner in which these helium flashes secularly evolve. In addition, we have found distinct characteristics of the light curves of these SNIa progenitors that may serve to identify and predict systems which may lead to SNIa.

Seminar Organizer: Dr. Ravit Heled