TITLE:   GCN CIRCULAR
NUMBER:  33490
SUBJECT: GRB 230321A: Fermi GBM Final Real-time Localization
DATE:    23/03/21 04:32:02 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 04:21:43 UT on 21 Mar 2023, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 230321A (trigger 701065308.721614 / 230321182).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 74.8, Dec = 28.0 (J2000 degrees, equivalent to J2000 04h 59m, 28d 00'), with a statistical uncertainty of 6.2 degrees.

The angle from the Fermi LAT boresight is 53.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230321182/quicklook/glg_skymap_all_bn230321182.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/bn230321182/quicklook/glg_healpix_all_bn230321182.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2023/bn230321182/quicklook/glg_lc_medres34_bn230321182.gif