{
  "format": "text/plain",
  "submitter": "rhamburg@usra.edu",
  "circularId": 44751,
  "eventId": "GRB 260531C",
  "subject": "GRB 260531C: Fermi GBM Final Localization Correction",
  "submittedHow": "web",
  "bibcode": "2026GCN.44751....1F",
  "createdOn": 1780271841155,
  "body": "The Fermi GBM team reports the detection of a likely SHORT GRB.\n\n\"At 21:14:58.91 UT on 31 May 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260531C (trigger 801954903/260531885). This trigger was initially classified as Below Horizon by the flight software, but is in fact a GRB.\n\nThe on-ground calculated location, using the Fermi GBM trigger data, is RA = 40.6, Dec = 36.2 (J2000 degrees, equivalent to J2000 2h 42m, +36d 12'), with a statistical uncertainty of 11.6 degrees.\n\nThe angle from the Fermi LAT boresight is 82 degrees.\n\nThe skymap can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260531885/quicklook/glg_skymap_all_bn260531885.png\n\nThe HEALPix FITS file, including the estimated localization systematic, can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260531885/quicklook/glg_healpix_all_bn260531885.fit\n\nThe GBM light curve can be found here: https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260531885/quicklook/glg_lc_medres34_bn260531885.gif\""
}