GCN Circular 42700
Subject
GRB 251116A: Fermi GBM Final Real-time Localization
Event
Date
2025-11-16T02:10:44Z (3 days 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 02:00:04 UT on 16 Nov 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 251116A (trigger 784951209.245526 / 251116083).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 27.3, Dec = -24.8 (J2000 degrees, equivalent to J2000 01h 49m, -24d 48'), with a statistical uncertainty of 4.5 degrees.
The angle from the Fermi LAT boresight is 30.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251116083/quicklook/glg_skymap_all_bn251116083.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/bn251116083/quicklook/glg_healpix_all_bn251116083.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251116083/quicklook/glg_lc_medres34_bn251116083.gif