GCN Circular 40701
Subject
GRB 250612B: BALROG localization (Fermi Trigger 771424081 / GRB 250612519)
Date
2025-06-12T13:17:08Z (3 days ago)
Edited On
2025-06-12T14:03:14Z (2 days ago)
From
Jochen Greiner at MPE <jcgrog@mpe.mpg.de>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov> on behalf of Jochen Greiner at MPE <jcg@mpe.mpg.de>
Via
email
T. Preis (University of Innsbruck) & J. Greiner (MPE Garching) report:
The public trigdat data of the Fermi Gamma-ray Burst Monitor (GBM) trigger
771424081 at 12:27:56 on 12 June 2025 were automatically fitted for spectrum
and sky location with BALROG (Burgess et al. 2018, MNRAS 476, 1427;
Berlato et al. 2019, ApJ 873, 60).
The best-fit position is:
RA(2000.0) = 226.1 deg
Decl.(2000.0) = -28.9 deg
The 1 sigma statistical error radius is 2.4 deg.
We estimate an additional systematic error of 1 deg.
This is consistent in time and position with the Einstein Probe detection of the X-ray transient EP 250612a (GCN 40700).
Further details are available at:
https://grb.mpe.mpg.de/grb/GRB250612519/
The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB250612519/healpix
The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB250612519/json