GRBAlpha, GRBBeta

GRBAlpha [BME]

GRBAlpha is an 1U CubeSat type nanosatellite mission to demonstrate the detector technology and electronics for the future “Cubesats Applied for MEasuring and LOcalising Transients” (CAMELOT) mission, which is a planned constellation of nanosatellites providing all-sky coverage with high sensitivity and localisation accuracy following detections of gamma-ray transients.

The detection and characterization of gamma-ray bursts is one of the most exciting fields in astronomy and it became even more prominent after the first detection of gravitational waves. However, simultaneous all-sky coverage and accurate localization are still challenging and this is where nano-satellites can play an essential role in the near future. One of such mission initiatives, Cubesats Applied for MEasuring and LOcalising Transients (CAMELOT) aims to fill this gap by providing gamma-ray transient detection via a fleet of 3U CubeSats.

The detector design for this mission is new in many aspects, including its full implementation at CubeSat level and the employment of SiPM detectors by Hamamatsu, called multi-pixel photon counter (MPPC). Compared to the final CAMELOT design, GRBAlpha will have a reduced effective scintillating surface area by a factor of 1/8 on a single piece of caesium-iodine, while keeping two of the MPPC linear arrays as a dualchannel redundant readout detector – where all of these, including the satellite platform electronics fit in an 1U CubeSat frame. In all other aspects, the payload side of GRBAlpha is identical to that of CAMELOT. Therefore, the comparison of the observed light curves provided by GRBAlpha with the existing gamma-ray observatories (Fermi, Swift) can validate the timing-based localization method, including estimates on the precision, accuracy and the spectral sensitivity. The higher level of integration and small size imply a simple attitude determination and control system (ADCS), however, we intend to test independent means of attitude recovery with a sub-degree accuracy.

A second satellite, GRBBeta, is to be flown on the maiden flight of the Ariane-62 launch vehicle.