GCN Circular 42719
Subject
GRB 251117A: Fermi GBM Final Localization Correction
Event
Date
2025-11-17T13:55:50Z (4 days ago)
From
Elisabetta Bissaldi at Politecnico and INFN Bari <elisabetta.bissaldi@ba.infn.it>
Via
Web form
The Fermi GBM team reports the detection of a likely SHORT GRB.
At 12:19:52.14 UT on 17 November 2025, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 251117A (trigger 785074797/251117514).
This trigger was initially classified as Below horizon by the flight software,
but is in fact due to a GRB.
The on-ground calculated location, using the Fermi GBM trigger data,
is RA = 335.05, Dec = 5.01 (J2000 degrees, equivalent to J2000 22h 20m, +05d 00'),
with a statistical uncertainty of 4.40 degrees.
The angle from the Fermi LAT boresight is 52 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251117514/quicklook/glg_skymap_all_bn251117514.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/bn251117514/quicklook/glg_healpix_all_bn251117514.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251117514/quicklook/glg_lc_medres34_bn251117514.gif