GCN Circular 39269
Subject
EP250207A: Upper limits from Fermi-GBM Observations
Date
2025-02-10T15:39:25Z (3 months ago)
From
mariaedvige.ravasio@ru.nl
Via
Web form
M. E. Ravasio (Radboud Univ.), E. Burns (LSU), and P.G. Jonker (Radboud Univ.) report on behalf of the Fermi-GBM Team:
Fermi-GBM had full spatial coverage of the transient EP250207A detected by EP-WXT (Li et al., GCN 39224), identified as a stellar flare (Levan et al., GCN 39218, O'Connor et al., GCN 39219, Li et al., GCN 39224). There was no Fermi-GBM onboard trigger around the EP trigger time T0=2025-02-07T15:51:17 UTC.
The GBM targeted search [1], the most sensitive, coherent search for GRB-like signals, was run in the time interval [T0-50;T0+500] s, seeking signals between 64 ms and 32.768 s in duration. No signal consistent with the EP transient both temporally and spatially is identified, as confirmed by visual inspection of the data.
Assuming a “soft” spectral template (Band function with Epeak = 70 keV, alpha = -1.9, beta = -3.7), and a duration of 8.192 s, we derive a sky-averaged flux upper limit of 2.8e-08 erg/cm2/s in the energy band 10-1000 keV.
[1] Goldstein et al. 2019 arXiv:1903.12597