TITLE:   GCN CIRCULAR
NUMBER:  40814
SUBJECT: GRB 250623A: Fermi GBM Final Real-time Localization
DATE:    25/06/23 16:21:45 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 16:11:12 UT on 23 Jun 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250623A (trigger 772387877.080294 / 250623674).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 233.4, Dec = -6.0 (J2000 degrees, equivalent to J2000 15h 33m, -6d 00'), with a statistical uncertainty of 10.2 degrees.

The angle from the Fermi LAT boresight is 68.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250623674/quicklook/glg_skymap_all_bn250623674.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250623674/quicklook/glg_healpix_all_bn250623674.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250623674/quicklook/glg_lc_medres34_bn250623674.gif