TITLE: GCN CIRCULAR NUMBER: 43759 SUBJECT: EP260214a / GRB 260214A: Fermi-GBM Sub-Threshold Detection DATE: 26/02/15 20:20:37 GMT FROM: mariaedvige.ravasio@ru.nl M. E. Ravasio (Radboud Univ.), P.G. Jonker (Radboud Univ.) and E. Burns (LSU), R. Hamburg (USRA) report on behalf of the Fermi-GBM Team: Fermi-GBM had full spatial and temporal coverage of the transient EP260214a detected by EP-WXT (Li et al., GCN 43742, Li et al., GCN 43751). There was no Fermi-GBM onboard trigger around the EP refined starting time T0=2026-02-14T20:37:00 (UTC). The GBM Targeted Search [1], the most sensitive, coherent search for GRB-like signals, was run in the time interval [-50;+500] s from the EP T0. A weak transient signal was found most significantly at ~T0+35 s on a 16 s timescale, with a false alarm rate of 2.27e-04 Hz. The localisation is consistent with the EP one, with a spatial association probability of 87.4%. Among the three spectral templates tested, the transient was best-fit with a "soft" spectrum (i.e., a Band function with Epeak = 70 keV, alpha = -1.9, beta = -3.7) for a GRB. [1] Goldstein et al. 2019 arXiv:1903.12597 View this GCN Circular online at https://gcn.nasa.gov/circulars/43759. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...