TITLE:   GCN CIRCULAR
NUMBER:  34608
SUBJECT: GRB 230903A: Fermi GBM Final Real-time Localization
DATE:    23/09/03 17:33:32 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 17:22:58 UT on 3 Sep 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230903A (trigger 715454583.81493 / 230903724).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 13.4, Dec = -13.5 (J2000 degrees, equivalent to J2000 00h 53m, -13d 30'), with a statistical uncertainty of 16.6 degrees.

The angle from the Fermi LAT boresight is 70.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230903724/quicklook/glg_skymap_all_bn230903724.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/bn230903724/quicklook/glg_healpix_all_bn230903724.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230903724/quicklook/glg_lc_medres34_bn230903724.gif

