TITLE:   GCN CIRCULAR
NUMBER:  33564
SUBJECT: GRB 230404A: Fermi GBM Final Real-time Localization
DATE:    23/04/04 23:10:23 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 23:00:07 UT on 4 Apr 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230404A (trigger 702342012.327256 / 230404958).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 139.8, Dec = -3.5 (J2000 degrees, equivalent to J2000 09h 19m, -3d 30'), with a statistical uncertainty of 3.5 degrees.

The angle from the Fermi LAT boresight is 56.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230404958/quicklook/glg_skymap_all_bn230404958.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/bn230404958/quicklook/glg_healpix_all_bn230404958.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230404958/quicklook/glg_lc_medres34_bn230404958.gif