GCN Circular 30233

P. Veres (UAH), B. Hristov (UAH) and C. Fletcher (USRA) and C. Meegan
(UAH) report on behalf of the Fermi GBM Team:

"At 15:03:42.75 UT on 10th of June 2021, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 210610A (trigger 645030227 / 210610628).

The burst was also detected by the Swift/BAT (Page et al., GCN 30160
Not found
 
 
).
The GBM on-ground location is consistent with the Swift position.

The angle from the Fermi LAT boresight at the GBM trigger time is 67 degrees.

The GBM light curve consists of two pulses with a duration (T90) of
about 8 s (50-300 keV). The time-averaged spectrum from T0-3.1 s to
T0+4.6 s is adequately fit by a power law function with an exponential
high-energy cutoff.  The power law index is -1.11 +/- 0.15 and the
cutoff energy, parameterized as Epeak, is 247 +/- 74 keV.


The event fluence (10-1000 keV) in this time interval is (1.78 +/-
0.23)E-6 erg/cm^2. The 1-sec peak photon flux measured starting from
T0+0.7 s in the 10-1000 keV band is 3.6 +/- 0.3 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/"