Speaker: Rahul Jayaramen (MIT)
Time-Domain Astrophysics with the Transiting Exoplanet Survey Satellite
The Transiting Exoplanet Survey Satellite (TESS) has transformed time-domain astronomy, offering new insights into both stellar phenomena and extragalactic transients like gamma-ray bursts (GRBs). In my talk, I will cover two key topics:
Binary star Asteroseismology: TESS has discovered a new class of pulsating star located in close binaries (with periods of less than 2 days). I will explore the evolution of our understanding of these so-called “tidally tilted pulsators” (TTPs) over the past five years, since the discovery of HD 74423, the first such star. I will specifically focus on our current interpretation—that the class of so-called TTPs can be explained through models invoking pulsation modes about all three axes of a star. These tidally distorted, pulsating stars can provide unique insights into the pulsator’s interior structure and evolutionary state.
Gamma-ray Bursts in TESS: The early-time optical behavior of GRBs has historically been challenging to observe from the ground; however, there exists evidence for a prompt optical flash that accompanies the high-energy emission from GRBs. I will discuss my work using TESS to characterize optical emission from GRBs. In particular, I will focus on my analysis of GRB light curves in TESS, and constraints on physical parameters derived solely from TESS data. Then, I will highlight my current project investigating the relationship between the high-energy emission and the optical flash. This work has not only led to the first-ever limits on prompt optical emission from short GRBs, but has also generated further questions about its origin.
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