GCN Circular 44031
Subject
GRB 260316B: Fermi GBM Final Real-time Localization
Event
Date
2026-03-16T17:23:26Z (23 days ago)
Edited On
2026-03-17T17:11:06Z (22 days ago)
From
Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>
Edited By
Judith Racusin at NASA/GSFC <judith.racusin@nasa.gov>
Via
email
The Fermi GBM team reports the detection of a likely LONG GRB
At 17:12:52 UT on 16 Mar 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260316B (trigger 795373977.681026 / 260316717).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 305.5, Dec = -79.3 (J2000 degrees, equivalent to J2000 20h 22m, -79d 17'), with a statistical uncertainty of 3.2 degrees.
The angle from the Fermi LAT boresight is 81.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260316717/quicklook/glg_skymap_all_bn260316717.png
The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260316717/quicklook/glg_healpix_all_bn260316717.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260316717/quicklook/glg_lc_medres34_bn260316717.gif