Contributed Talk - Splinter Stellar

Friday, 25 September 2020, 16:41   (virtual room M)

3d simulations of the later phase of a merger-burst ILOT

Amir Michaelis
Ariel University

Luminous Red Nova (LRN) are eruptive stellar events, thought to be the result of merging stars. Best known examples for such merger-bursts are the eruptions of V838 Mon in 2002 and V1309 Sco in 2008. LRNe are a subclass of the Intermediate Luminosity Optical Transient (ILOTs) -- stellar eruptions that are gravitationally powered. In the merger scenario a main sequence star (primary) will interact with a less dense star of equal mass or less massive (secondary), destroying the latter in the process. This arrangement can occur if the secondary is a pre-main-sequence star or just on the verge of ZAMS. We assume the late stage of such a merger will result in a thick belt of shredded secondary matter around the primary, and simulate the evolution of the merger-burst transient from that point. We initialize the simulation with a $8Msun$ primary and a $1Msun$ thick accretion disk rotate with Keplerian velocities. We find that the disk is unstable and most of the matter is depleted in about $25-40days$. We find that part of the disk is accreted onto the star, and calculate the expected light curve of the system for different inclination angles. We find similarities between the synthetic light curve and the characteristic light curve of ILOTs: more then one peak in the first ~10 days as a results of instabilities, and a steep decline as the result of the disk depletion.