TITLE: GCN CIRCULAR NUMBER: 40050 SUBJECT: GRB 250404A: Fermi GBM Final Real-time Localization DATE: 25/04/04 14:30:25 GMT FROM: Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov> The Fermi GBM team reports the detection of a likely LONG GRB At 14:19:46 UT on 4 Apr 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250404A (trigger 765469191.347644 / 250404597). The on-ground calculated location, using the Fermi GBM trigger data, is RA = 123.4, Dec = 34.1 (J2000 degrees, equivalent to J2000 08h 13m, 34d 06'), with a statistical uncertainty of 1.2 degrees. The angle from the Fermi LAT boresight is 42.0 degrees. The skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250404597/q... The HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250404597/q... The GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250404597/q... View this GCN Circular online at https://gcn.nasa.gov/circulars/40050. --- To unsubscribe, open this link in a web browser: https://gcn.nasa.gov/unsubscribe/eyJhbGciOiJIUzI1NiJ9.eyJlbWFpbCI6InZzbmV0LW...