GCN Circular 38536

C. McKenna, D. Murphy, C. de Barra, A. Ulyanov, P. McDermott, M. Doyle, R. Dunwoody, J. Mangan, G. Finneran, 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:

EIRSAT-1 reports the tentative detection of the long gamma-ray burst GRB 241207A by the Gamma-ray Module (GMOD) instrument, which was also detected by Fermi GBM (GCN 38454

The GMOD light curve for GRB 241207A with 1.2s binning shows a long burst with multiple pulses. The timing of the pulses is in broad agreement with those seen in the Fermi GBM lightcurve. The spacecraft location at the time of detection was 4.325 N, 19.089 E at an altitude of 460.2 km.

The GMOD light curve for this event can be found here: https://grb.eirsat1.ie/241207A/241207A_LC_onboard_preliminary.png

EIRSAT-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.