[vsnet-grb-info 25797] GRB 200530A: Fermi GBM detection

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  27897
SUBJECT: GRB 200530A: Fermi GBM detection
DATE:    20/06/06 23:30:30 GMT
FROM:    Joshua Wood at MSFC/Fermi-GBM  <joshua.r.wood at nasa.gov>

J. Wood (NASA/MSFC) and C. Meegan (UAH) report on behalf of the Fermi GBM Team:

"At 00:44:10.57 UT on 30 May 2020, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 200530A (trigger 612492255 / GBM200530031),
which was also detected by the Fermi/LAT (Longo et al. 2020, GCN 27891)
The Fermi GBM Final Real-time Localization is consistent with the LAT position.

The angle from the Fermi LAT boresight at the GBM trigger time is 41 degrees.

The GBM light curve shows a multi-peaked structure
with a duration (T90) of about 23 s (50-300 keV).
The time-averaged spectrum from T0-1.5 s to T0+28.2 s is
best fit by a power law function with an exponential high-energy cutoff.
The power law index is -0.55 +/- 0.02 and the cutoff energy, parameterized
as Epeak, is 178 +/- 4 keV.

The event fluence (10-1000 keV) in this time interval is
(2.27 +/- 0.03)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+10.0 s in the 10-1000 keV band
is 10.9 +/- 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/"