{
  "circularId": 39541,
  "submittedHow": "web",
  "body": "G. Finneran, C. McKenna, D. Murphy, C. de Barra, A. Ulyanov, P. McDermott, M. Doyle, R. Dunwoody, J. Mangan, G. Corcoran, L. Cotter, A. Empey, J. Fisher, F. Gibson Kiely, J. Thompson, D. McKeown, A. Martin-Carrillo, L. Hanlon, S. McBreen, on behalf of the EIRSAT-1 team: \n\nEIRSAT-1 reports the detection of the long gamma-ray burst GRB250225B by the Gamma-ray Module (GMOD) instrument, which was also detected by Swift BAT (GCN 39473), SVOM GRM (GCN 39493), Konus-Wind (GCN 39498), Fermi GBM (GCN 39502)  and INTEGRAL SPI-ACS (GCN 39517). The GMOD detection was made starting at 2025-02-25 19:39:13.1 UTC.\n\nThe GMOD light-curve for GRB250225B with 1.2s binning shows a peak consistent with the first peak seen by SVOM GRM, with a tentative detection of the second peak at around 60 seconds.\n\nThe spacecraft location at the time of detection was 31.703 N, 135.873 W, at an altitude of 425.8km.\n\nThe GMOD light curve for this event can be found here: \nhttps://grb.eirsat1.ie/250225B/250225B_LC_onboard_preliminary.png \n\nEIRSAT-1 is Ireland’s first satellite (Doyle et al. Proceedings of the 4th SSEA, 2022). It is a 2U CubeSat and carries onboard a number of experiments including the Gamma-Ray Module (GMOD), a novel, compact, gamma-ray detector (Murphy et al, Experimental Astronomy, 53, 961–990, 2022). GMOD consists of a 25 mm × 25 mm × 40 mm Cerium Bromide scintillator coupled to SiPMs and is designed to detect gamma-ray bursts in the ~ 60 keV - 1.5 MeV range. EIRSAT-1 was developed in University College Dublin with support from ESA’s Fly Your Satellite! programme and was launched on 1st December 2023.",
  "subject": "GRB 250225B: EIRSAT-1 GMOD Detection",
  "format": "text/plain",
  "eventId": "GRB 250225B",
  "createdOn": 1740777734135,
  "submitter": "Gabriel Finneran at School of Physics and Centre for Space Research, University College Dublin <gabriel.finneran@ucdconnect.ie>",
  "bibcode": "2025GCN.39541....1F"
}