BurstCube: A CubeSat for Gravitational Wave Counterparts

BurstCube is a 6U (10 x 20 x 30 cm) CubeSat designed to detect and localize gamma-ray bursts (GRBs) in the 50 keV to 1 MeV energy band, scheduled to launch in 2023. Coincident detection of gravitational waves (GWs) and GRBs is a specific form of multi-messenger astrophysics that provides more context to GW measurements, namely constraining the neutron star equation of state and testing fundamental physics, while also probing the origin of GRB prompt emission. Full sky coverage in the gamma-ray regime is required to increase the likelihood of coincident detection. BurstCube will expand sky coverage and provide electromagnetic counterparts to GW events detected by LIGO, Virgo, and KAGRA as well as other gamma-ray transients. The instrument package consists of four individual CSI (TI) scintillating detectors positioned at 45º relative to each other, read out by SiPMs. This orientation allows for localizations and full unocculted sky coverage. We present the current status of the mission and describe the instrument, operation, and software pipeline in detail.