TITLE:   GCN CIRCULAR
NUMBER:  38839
SUBJECT: GRB 250107B: Fermi GBM Final Real-time Localization
DATE:    25/01/07 11:44:24 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 11:34:04 UT on 7 Jan 2025, the Fermi Gamma-ray Burst Monitor (GBM) triggered and located GRB 250107B (trigger 757942449.293284 / 250107482).

The on-ground calculated location, using the Fermi GBM trigger data, is RA = 110.8, Dec = 59.6 (J2000 degrees, equivalent to J2000 07h 23m, 59d 36'), with a statistical uncertainty of 25.9 degrees.

The angle from the Fermi LAT boresight is 69.0 degrees.

The skymap can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250107482/quicklook/glg_skymap_all_bn250107482.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/bn250107482/quicklook/glg_healpix_all_bn250107482.fit

The GBM light curve can be found here:
https://heasarc.gsfc.nasa.gov/FTP/fermi/data/gbm/triggers/2025/bn250107482/quicklook/glg_lc_medres34_bn250107482.gif