[vsnet-grb-info 25893] GRB 200619A: Fermi GBM observation

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27993
SUBJECT: GRB 200619A: Fermi GBM observation
DATE:    20/06/19 21:15:01 GMT
FROM:    Cori Fletcher at USRA  <cfletcher at usra.edu>

C. Fletcher (USRA) and C. Meegan (UAH)
report on behalf of the Fermi GBM Team:

"At 02:36:11.67 UT on 19 June 2020, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 200619A (trigger 614226976 / 200619108).
This burst was also detected by the AGILE satellite (A. Ursi et al. 2020, GCN 27991)
and Insight-HXMT/HE (S. Xiao et al. 2020, GCN 27985).

The on-ground calculated location, using the GBM trigger
data, is RA = 101.4, DEC = 56.7 (J2000 degrees,
equivalent to 06h 45m, 56d 44'), with a statistical uncertainty
of 4.0 degrees (radius, 1-sigma containment,
statistical only; there is additionally a systematic
error which we have characterized as a core-plus-tail model, with 90% of
GRBs having a 3.7 deg error and a small tail suffering a larger than 10 deg
systematic error. [Connaughton et al. 2015, ApJS, 216, 32] ).

The angle from the Fermi LAT boresight at the GBM trigger time is 103 degrees.

The GBM light curve consists of a single bright peak
with a duration (T90) of about 29 s (50-300 keV).
The time-averaged spectrum from T0+0.003 s to T0+29.120 s is
best fit by a power law function with an exponential
high-energy cutoff.  The power law index is -0.82 +/- 0.06 and
the cutoff energy, parameterized as Epeak, is 1268 +/- 199 keV.

The event fluence (10-1000 keV) in this time interval is
(1.42 +/- 0.04)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+0.064 s in the 10-1000 keV band
is 4.8 +/- 0.4 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/"