GCN Circular 42224
Subject
GRB 251013D: Fermi GBM Final Real-time Localization
Event
Date
2025-10-13T18:27:33Z (2 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 18:17:00 UT on 13 Oct 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 251013D (trigger 782072225.388414 / 251013762).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 44.4, Dec = 10.2 (J2000 degrees, equivalent to J2000 02h 57m, 10d 11'), with a statistical uncertainty of 5.4 degrees.
The angle from the Fermi LAT boresight is 73.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251013762/quicklook/glg_skymap_all_bn251013762.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/bn251013762/quicklook/glg_healpix_all_bn251013762.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn251013762/quicklook/glg_lc_medres34_bn251013762.gif