MATs (Monday Afternoon Talks), 05/08/2023 – Speakers: Evan Bauer, CfA & Ryan Lau, NSF NOIR Lab
MATs (Monday Afternoon Talks)
3:00pm – Evan Bauer
Modeling Runaway Donor Stars to Understand Supernovae in White Dwarf Binaries
In the quest to understand the physics and astrophysics of how Type Ia supernovae occur, we have recently turned attention toward better understanding the physics of mass transfer and detonation in double white dwarf binary systems. These systems produce hypervelocity runaway stars that preserve evidence of the thermonuclear supernova that destroyed their former companions. This evidence comes in the form of their extreme outlier velocities, unusual thermal state, and strange polluted surface compositions. In this talk, I’ll briefly describe where we stand with the discovery of these hypervelocity stellar remnants, what they have already taught us about thermonuclear supernovae, and what we have left to learn through detailed modeling of their unusual composition and structure.
3:30pm – Ryan Lau
Tracing Stellar Explosions and Cosmic Dust
Dust grains are the seeds of star and planet formation and are direct tracers of the chemical enrichment of the Universe. Although the origins of dust are unclear, its abundance in some of the earliest galaxies less than 1 Gyr after the Big Bang indicate that dust formation must be intrinsically linked to the brief but extreme lives and deaths of massive stars. Driven by the resurgence of optical and infrared (IR) time-domain surveys, emerging classes of IR-luminous stellar transient events have been identified and present potential sites of substantial dust formation. However, their role as dust and chemical factories has been largely unexplored due to observational limitations on discovering and characterizing such dust-obscured outbursts. This situation is now dramatically changing with the launch of JWST and the upcoming Legacy Survey of Space and Time (LSST) with the Vera C. Rubin Observatory. In this talk, I will present some of the first results in this changing landscape with JWST focusing on dust-formation outbursts from carbon-rich Wolf-Rayet (WC) stars that highlight their role as potential factories of carbon-rich dust. Lastly, I will discuss a new exploration of IR transient science enabled by JWST and the NOIRLab Programs: Rubin, Gemini, Mid-Scale Observatories, and the Community Science & Data Center. A coordinated IR transient and follow-up campaign with these platforms will allow us to trace the explosive origins of dust and chemical enrichment of the interstellar medium from the emerging classes of IR-luminous stellar transients.
Host: Josh Burrow
Speakers
- Evan Bauer, CfA
- Ryan Lau, NSF NOIR Lab