{
  "circularId": 44747,
  "submittedHow": "email",
  "subject": "GRB 260531B: Fermi GBM Final Real-time Localization",
  "body": "The Fermi GBM team reports the detection of a likely LONG GRB\n\nAt 13:57:59 UT on 31 May 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260531B (trigger 801928684.989378 / 260531582).\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 282.6, Dec = 6.4 (J2000 degrees, equivalent to J2000 18h 50m, 6d 24'), with a statistical uncertainty of 2.2 degrees.\n\nThe angle from the Fermi LAT boresight is 48.0 degrees.\n\nThe skymap can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260531582/quicklook/glg_skymap_all_bn260531582.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260531582/quicklook/glg_healpix_all_bn260531582.fit\n\nThe GBM light curve can be found here:\nhttps://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260531582/quicklook/glg_lc_medres34_bn260531582.gif\n",
  "submitter": "Fermi GBM Team at MSFC/Fermi-GBM <do_not_reply@GIOC.nsstc.nasa.gov>",
  "eventId": "GRB 260531B",
  "createdOn": 1780236517965
}