BlackCAT Short Burst Detection Expectations via Prompt and Extended Emission Simulation

open_access
Open Access
Author:
Royer, Luke
Area of Honors:
Astronomy and Astrophysics
Degree:
Bachelor of Science
Document Type:
Thesis
Thesis Supervisors:
Derek Brindley Fox, Thesis Supervisor
William Nielsen Brandt, Thesis Honors Advisor
Keywords:
astronomy
astrophysics
gamma-ray bursts
short gamma-ray bursts
high-energy astrophysics
simulation
BlackCAT
X-ray
gamma-ray
Abstract:
Launched in January 2026 and currently undergoing on-orbit validation, Penn State’s Black Hole Coded Aperture Telescope (BlackCAT) is a NASA-funded CubeSat (6U) mission dedicated to high-energy transient discovery and wide-sky X-ray monitoring. While BlackCAT’s rate of burst detections, and expected redshift distribution, for long-duration gamma-ray bursts (long bursts) have previously been estimated from high-fidelity simulations using prototype flight software, the rate of detections and observed redshift and luminosity distributions for short-duration gamma- ray bursts (short bursts) have not. While expected to account for a distinct minority (∼<10%) of BlackCAT gamma-ray bursts, the short bursts are of particular scientific interest due to their origins in compact object mergers. Such compact object mergers have the potential to be detected as gravitational wave events, as with the multimessenger transient GW 170817 / GRB 170817A, and have been shown to be important sites of r-process nucleosynthesis. Through modeling of the short burst population, using template burst lightcurves and spectra from the Swift BAT catalog, and applying BlackCAT prototype flight software as in previous studies, we explore BlackCAT’s sensitivity to short GRBs and derive predicted redshift and luminosity distributions. These are not only the first simulations of short burst detection for BlackCAT but, to our knowledge, the first simulations of the detectability of short bursts by X-ray instrumentation of any sort that explore the detectability of short bursts with and without the extended, softer emission that is observed to accompany a significant fraction of short bursts. We find an expected rate of 2.8 detected bursts per year on-orbit for BlackCAT. Accounting for the extended emission of some short bursts increases detection sensitivity by a factor of ≈4, allowing these bursts to be detected to greater distances and lower luminosities