GCN Circular 41545
Subject
GRB 250826A: Fermi GBM Final Real-time Localization
Event
Date
2025-08-26T07:34:29Z (a month ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
Via
email
The Fermi GBM team reports the detection of a likely LONG GRB
At 07:24:01 UT on 26 Aug 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250826A (trigger 777885846.969916 / 250826308).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 141.8, Dec = 34.7 (J2000 degrees, equivalent to J2000 09h 27m, 34d 42'), with a statistical uncertainty of 3.6 degrees.
The angle from the Fermi LAT boresight is 40.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250826308/quicklook/glg_skymap_all_bn250826308.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250826308/quicklook/glg_healpix_all_bn250826308.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250826308/quicklook/glg_lc_medres34_bn250826308.gif