TITLE:   GCN CIRCULAR
NUMBER:  45574
SUBJECT: Fermi GBM Sub-Threshold Detection of GRB 260915A
DATE:    26/09/15 04:56:50 GMT
FROM:    rhamburg@usra.edu

R. Hamburg (USRA) reports on behalf of the Fermi-GBM Team:

SVOM ECLAIRs detected GRB 260915A on 2026-09-15 at 01:12:03 UTC (GCN 45570). There was no Fermi-GBM onboard trigger around this time.

The GBM Targeted Search [1], the most sensitive coherent search for GRB-like signals in GBM, identified a spatially-consistent transient at 2026-09-15T01:12:01.517 UTC. The Targeted Search event is found most significantly on the 32.768 s timescale with a false alarm rate of 8.3e-5 Hz. The Fermi-MET of this transient is 811127526.517 s. Additionally, the Targeted Search event was found with the highest significance using a normal GRB spectrum (Band function with Epeak = 230 keV, alpha = -1.0, beta = -2.3).

[1] Goldstein et al. 2019 arXiv:1903.12597