TITLE:   GCN CIRCULAR
NUMBER:  44942
SUBJECT: GRB 260614B: Fermi GBM Observation
DATE:    26/06/14 21:57:48 GMT
FROM:    Eva M. Palafox at INAOE <eva.palafox@gmail.com>

E. Palafox (INAOE-Mexico) reports on behalf of the Fermi Gamma-ray Burst Monitor Team:

"At 13:49:53.52 UT on 14 June 2026, the Fermi Gamma-ray Burst Monitor (GBM)
triggered and located GRB 260614B (trigger 803137798/260614576).
which was also detected by SVOM/ECLAIRs (Godet et al. 2026, GCN 44938).
The Fermi GBM on-ground location is consistent with the SVOM/ECLAIRs position.

The angle from the Fermi LAT boresight is 31 degrees.

The GBM light curve consists of a single emission episode with a duration (T90)
of about 30 s (50-300 keV). The time-averaged spectrum
from T0-13 to T0+34 s is best fit by
a power law function with an exponential high-energy cutoff.
The power law index is -0.78 +/- 0.03 and the cutoff energy,
parameterized as Epeak, is 510 +/- 10 keV.

The event fluence (10-1000 keV) in this time interval is
(2.20 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+13 s in the 10-1000 keV band is 5.7 +/- 0.2 ph/s/cm^2.

The spectral analysis results presented above are preliminary;
final results will be published in the GBM GRB Catalog:
https://heasarc.gsfc.nasa.gov/W3Browse/fermi/fermigbrst.html

For Fermi GBM data and info, please visit the official Fermi GBM Support Page:
https://fermi.gsfc.nasa.gov/ssc/data/access/gbm/"