TITLE:   GCN CIRCULAR
NUMBER:  34826
SUBJECT: GRB 231018A: Fermi GBM Final Real-time Localization
DATE:    23/10/18 12:40:39 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 12:30:10 UT on 18 Oct 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 231018A (trigger 719325015.663762 / 231018521).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 3.0, Dec = 50.7 (J2000 degrees, equivalent to J2000 00h 12m, 50d 42'), with a statistical uncertainty of 1.0 degrees.

The angle from the Fermi LAT boresight is 131.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231018521/quicklook/glg_skymap_all_bn231018521.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231018521/quicklook/glg_healpix_all_bn231018521.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn231018521/quicklook/glg_lc_medres34_bn231018521.gif