Using TESS as a Search Engine forGRB Progenitors

Gamma-ray bursts (GRBs) are the brightest electromagnetic events known to occur in the universe, and are characterized by brief flashes of gamma-ray energy concentrated from 0.1 to 1 MeV. In some GRB models, a supernova leaves behind a rotationally supported supermassive neutron star which then slowly shrinks through angular momentum loss via a wind. After a time period typically anticipated to be weeks to months, the configuration becomes unstable and collapses to a black hole, leading to the GRB. The possibility of such a SN progenitor to the (delayed) GRB motivates a search for such emission.

We used TESS fields to search for visible GRB progenitors. We first cross-referenced TESS FFI observations with Swift Burst Telescope (BAT) GRB detections, comparing each GRB detection to TESS observation dates to determine if that region of the sky was previously observed by TESS. We then analyzed candidates using aperture photometry to extract light curves and search for short-term brightening events. We also conducted background analysis on regions of the sky approximately 1 degree away from the candidate’s original position to evaluate the probability of observing such events in the absence of a GRB, from sources such as an otherwise undetected flaring M dwarf. Here we present results from a search of TESS Cycle 1 data.