GCN Circular 39138
Subject
GRB 250204A: Fermi GBM Final Real-time Localization
Date
2025-02-04T07:38:50Z (10 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 07:28:17 UT on 4 Feb 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250204A (trigger 760346902.4098 / 250204311).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 108.2, Dec = -23.8 (J2000 degrees, equivalent to J2000 07h 12m, -23d 48'), with a statistical uncertainty of 1.1 degrees.
The angle from the Fermi LAT boresight is 9.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250204311/quicklook/glg_skymap_all_bn250204311.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/bn250204311/quicklook/glg_healpix_all_bn250204311.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250204311/quicklook/glg_lc_medres34_bn250204311.gif