Optimizing the Search for Gamma-Ray Counterparts to Gravitational-Wave Observations
Abstract
Since discovering the first gamma-ray counterpart to a gravitational-wave (GW) signal in 2017, the Fermi Gamma-ray Burst Monitor (GBM) has been a leading instrument in detecting such counterparts to GW events. While events above a certain detection threshold "trigger" the flight software upon observation, copious non-triggering short gamma-ray bursts (SGRBs) are instead uncovered through a subthreshold search that analyzes data in a time window for potential events once the full data is downlinked to the ground. A primary objective of this project is to apply and test several changes to this targeted sub-threshold search on both real events and background noise. This is done by running the search on previously observed, Swift-coincident GRBs and on 100 random ten-second windows of background. Such adjustments to the search include adding a blackbody spectral template—allowing for an expansion of discovery space for SGRBs—and adjusting the instrument's energy channels that are included in the search. By investigating which configuration maximizes the detection statistic for real events and minimizes it for background noise, the results of the project will contribute to more effective and confident future detections of gamma-ray counterparts in collaborations with LIGO/Virgo, IceCube Neutrino Observatory, etc.
- Publication:
-
American Astronomical Society Meeting Abstracts #233
- Pub Date:
- January 2019
- Bibcode:
- 2019AAS...23324802L