The luminous red nova AT 2018bwo in NGC 45 and its binary yellow supergiant progenitor

New paper spearheaded by Nadia Blagorodnova and Jakub Klencki on Luminous red nova in NGC 45. For the first time, the progenitor of LRN was analyzed using binary star evolution tracks instead of single star tracks finding that the location exactly matches thermal-timescale (case B) mass transfer in a massive binary. The models suggest that quite a bit of mass (few Msun) was lost from the system in 100s of years before the merger. We take the structure of the final model of the primary and based on standard common envelope formalism predict how much mass should be ejected. We compare this prediction with inference from the transient, modeled as either scaled-down Type II-P or shock-interaction powered. We need transient models calibrated specifically for LRNe! We’re also somewhat puzzled by not seeing a lot of dust in the progenitor – something for future work.
https://arxiv.org/abs/2102.05662

About

We are interested in connecting theory, observations, and data modelling of time-domain phenomena in astronomy. This includes transients such as core-collapse supernovae and stellar mergers, persistent variable sources such as eclipsing binaries and pulsating stars, and stellar dynamics. We do (radiation)(magneto)hydrodynamics on supercomputers, semi-analytic models, and machine learning of astronomical data. Come meet us at Science coffee every Tuesday and Thursday at 2.30pm in KVAS room at ITP.

We are supported by the ERC Starting grant Cat-In-hAT to develop new computational methods to study binary star mergers, common envelope, and the associated transients. We are also support by Czech Science Foundation to study mass transfer in binaries. In the past, we received Czech-American collaboration grant from the Czech Ministry of Education, Youth, and Sports to participate in the ASAS-SN survey and the Primus award PRIMUS/SCI/17 from the Charles University.