TITLE:   GCN CIRCULAR
NUMBER:  45056
SUBJECT: GRB 260629A: Fermi GBM Final Real-time Localization
DATE:    26/06/29 15:19:19 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 SHORT GRB

At 15:06:58 UT on 29 Jun 2026, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 260629A (trigger 804438423.955606 / 260629630).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 146.1, Dec = 70.6 (J2000 degrees, equivalent to J2000 09h 44m, 70d 35'), with a statistical uncertainty of 10.5 degrees.

The angle from the Fermi LAT boresight is 49.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260629630/quicklook/glg_skymap_all_bn260629630.png

The HEALPix FITS file, including the estimated localization systematic, can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260629630/quicklook/glg_healpix_all_bn260629630.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2026/bn260629630/quicklook/glg_lc_medres34_bn260629630.gif