About BurstCube

Publications:

• BurstCube refereed journals
• BurstCube in non-referenced publications

Mission Description:

The BurstCube mission is a 6U (10 cm × 20 cm × 30 cm) CubeSat mission to detect gamma-ray burst events to send rapid alerts and provide initial detection for events, with a special focus on short (<2 s) gamma-ray burst targets (sGRBs) and coincident observations with gravitational wave sources. After an initial six month mission span, operations may be extended for the duration of the spacecraft’s functionality.

Data is relayed to the ground routinely every 2–12 hours, but in the event of a special trigger event (such as a burst source detection), trigger data is downloaded within minutes via TDRSS. Onbaord storage of data also permits a number of requested time trigger events (RTTE) should investigators desire them after looking at the QuickLook data. The anticipated detection rate for sGRBs is 20 per year. The mission should also detect around 100 long GRBs per year, providing improved statistics for these sources.

The instrument hardware, and flight and ground software design builds off the heritage from Fermi’s Gamma-ray Burst Monitor (GBM) instrument.

BurstCube observed the full unocculted sky in the zenithal direction, using a set of four thallium-doped cesium iodide (CsI(Tl)) crystal detectors coupled to low-power silicon photomultipliers (SiPMs). The crystals are circular disks, 9 cm in diameter and 1.9 cm thick, mounted offset 45 degrees from zenith, with an array of 116 SiPMs behind each. The individual crystal and SiPMs units are refered to as single quarter detectors (SQDs). Each SQD is encased in an aluminium housing which is transparent to gamma rays. Since a gamma ray source produces more hits in an SQD on-axis than off-, relative signal detection from the combined SQDs provides directional information.

BurstCube develops a coarse location and relays that detection to the ground (through the TDRSS network) within minutes of detection. Roughly 90% of sGRBs are located to within 30° accuracy.

The mission operation timeframe matches observation runs with the LIGO gravitational wave detector to provide rapid EM counterpart locations to any GW events.

BurstCube Mission and Instrument References

• BurstCube: a CubeSat for gravitational wave counterparts
  Perkins, J et al., SPIE, 11444, 1X (2020)
• BurstCube: Calibrations
  Joens, A & BurstCube Team, HEAD, 19, 10835 (2022)