TITLE:   GCN CIRCULAR
NUMBER:  33721
SUBJECT: GRB 230503A: Fermi GBM Final Real-time Localization
DATE:    23/05/03 20:29:45 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 20:19:07 UT on 3 May 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230503A (trigger 704837952.436878 / 230503847).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 66.0, Dec = -48.7 (J2000 degrees, equivalent to J2000 04h 24m, -48d 42'), with a statistical uncertainty of 2.9 degrees.

The angle from the Fermi LAT boresight is 72.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230503847/quicklook/glg_skymap_all_bn230503847.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/bn230503847/quicklook/glg_healpix_all_bn230503847.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230503847/quicklook/glg_lc_medres34_bn230503847.gif