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GCN Circular 45465

Subject
GRB 260829A: BALROG localization (Fermi Trigger 809676494 / GRB 260829256)
Date
2026-08-29T06:34:56Z (4 days ago)
From
Jochen Greiner at MPE <jcgrog@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
809676494 at 06:08:09 on 29 Aug. 2026 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) = 240.0 deg
Decl.(2000.0) = -30.5 deg
The 1 sigma statistical error radius is 1.5 deg.
We estimate an additional systematic error of 2 deg.

Further details are available at:
https://grb.mpe.mpg.de/grb/GRB260829256/

The Healpix map can be downloaded from:
https://grb.mpe.mpg.de/grb/GRB260829256/healpix

The location parameters are available as JSON at:
https://grb.mpe.mpg.de/grb/GRB260829256/json

                        

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