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Gravitational Wave High-energy Electromagnetic Counterpart All-sky Monitor (GECAM)

GECAM logo

Launch Date: December 9, 2020

End of Operations: No specific requirement

Data Archives: GCN Classic

GECAM is a constellation of two small X-ray and gamma-ray all-sky observatories. These two microsatellites, denoted as GECAM-A and GECAM-B, are designed to operate on opposite sides of the Earth. Each GECAM satellite features a dome-shaped array of 25 Gamma-ray detectors (GRD) and 8 Charged particle detectors (CPD). Each satellite can monitor the all-sky un-occulted by the Earth, thus two satellites together could watch the entire sky. Due to unexpected anomalies in power supply system, GECAM-A has not been able to observe yet, and GECAM-B can observe about 10 hours per day since January 14, 2021, and about 21 hours per day since May 30, 2022.

InstrumentsEnergy RangeField of ViewLocalization
GECAM-B15 keV–5 MeV7.5 ster~1-10 deg (radius, stat, 68% containment)

GCN Notice Types in GCN Classic and GCN Classic Over Kafka: Detailed Descriptions and Examples


Yearly Trigger Rates:

GECAMGRBs, other transients, and non-astrophysical triggers~500

Real notices will have Trigger_Number values between 1 and 99999999. Test notices will have Trigger_Number values greater than or equal to 100000000.

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