GCN Circular 39876
Subject
GRB 250327A: Fermi GBM Final Real-time Localization
Date
2025-03-27T07:40:37Z (5 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 07:30:06 UT on 27 Mar 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250327A (trigger 764753411.32631 / 250327313).
The on-ground calculated location, using the Fermi GBM trigger data, is RA = 246.1, Dec = 62.3 (J2000 degrees, equivalent to J2000 16h 24m, 62d 17'), with a statistical uncertainty of 3.6 degrees.
The angle from the Fermi LAT boresight is 47.0 degrees.
The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250327313/quicklook/glg_skymap_all_bn250327313.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/bn250327313/quicklook/glg_healpix_all_bn250327313.fit
The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250327313/quicklook/glg_lc_medres34_bn250327313.gif