{
  "bibcode": "2025GCN.42104....1H",
  "body": "R. Hamburg (USRA) reports on behalf of the Fermi-GBM Team:\n\nThe SVOM/ECLAIRs detected GRB 250910A on 2025-09-10 at 03:16:10 UTC (GCN 41769). GRB 250910A was also detected by EP-WXT (GCN 41776) and has a measured redshift of z = 0.592 from the VLT/X-shooter (GCN 42031). There was no Fermi-GBM onboard trigger around this event time. An automated, blind search for gamma-ray bursts below the onboard triggering threshold in Fermi-GBM identified no candidates.\n\nThe GBM Targeted Search [1], the most sensitive GBM search for GRB-like signals, identified a transient starting 12.29 seconds after the ECLAIRs trigger time, most significantly on the 16 s timescale with a post-trials false alarm rate of 3.1e-04 Hz. The Targeted Search event was found with the highest significance using a \"soft\" GRB spectrum (i.e., Band function with Epeak = 70 keV, alpha = -1.9, and beta = -3.7), and the GBM localization was found to be spatially consistent with the ECLAIRs location and the X-ray and optical/NIR afterglow positions (GCN 41794, GCN 41798, GCN 41799). \n\n[1] Goldstein et al. 2019 arXiv:1903.12597",
  "submittedHow": "web",
  "circularId": 42104,
  "format": "text/plain",
  "submitter": "rhamburg@usra.edu",
  "eventId": "GRB 250910A",
  "subject": "Fermi GBM Sub-Threshold Detection of GRB 250910A",
  "createdOn": 1759541659393
}