[vsnet-grb-info 22606] GRB 190531B: Fermi GBM observations

[GCN Circulars]

TITLE:   GCN CIRCULAR
NUMBER:  24705
SUBJECT: GRB 190531B: Fermi GBM observations
DATE:    19/06/01 03:39:22 GMT
FROM:    Peter Veres at UAH  <veresp at gmail.com>

P. Veres and C. Meegan (both UAH) report on behalf of the Fermi GBM Team:

"At 20:10:12.14 UT on 31 May 2019, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 190531B (trigger 581026217 / 190531840, GCN
#24695), which was also detected by Fermi-LAT (GCN # 24701).

The GBM light curve consists of multiple peaks with a duration (T90) of
about 38.4 s (50-300 keV).

The time-averaged spectrum from T0 to T0+44.4 s is best fit by a Band
function with Epeak = 473 +/- 14 keV, alpha = -0.79 +/- 0.01, and beta =
-2.33 +/- 0.06.

The event fluence (10-1000 keV) in this time interval is (9.91 +/-
0.08)E-05 erg/cm^2. The 1-sec peak photon flux measured starting from
T0+31.2 s in the 10-1000 keV band is 27.7 +/- 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/"