GRB 210714A
GCN Circular 30467
Subject
Konus-Wind detection of GRB 210714A
Date
2021-07-18T14:11:31Z (4 years ago)
From
Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>
D. Frederiks, S. Golenetskii, A.Lysenko, A. Ridnaia,
D. Svinkin, A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
GRB 210714A (Fermi-GBM trigger 647942198 / MASTER optical afterglow detection: Lipunov et al., GCN 30466)
triggered Konus-Wind (KW) at T0=28598.602 s UT (07:56:38.602).
The burst light curve shows a bright, FRED-like pulse
which starts at ~T0-2.5 s, and has a total duration of ~80 s.
The emission is seen up to ~15 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB210714_T28598/
As observed by Konus-Wind, the burst had
a fluence of (9.6 �� 0.8)x10^-5 erg/cm^2 and
a 64-ms peak energy flux, measured from T0 + 1.664 s,
of (1.07 �� 0.10)x10^-5 erg/cm^2/s (both in the 20 keV - 10 MeV energy range).
The time-integrated spectrum (measured from T0 to T0+46.848 s)
is best fit in the 20 keV - 15 MeV range
by the GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -1.25 (-0.20,+0.49),
the high energy photon index beta = -1.83 (-0.06,+0.05),
the peak energy Ep = 145 (-60,+81) keV,
chi2 = 101/97 dof.
The spectrum near the peak count rate (measured from T0+0.256
to T0+5.888 s) is best fit in the 20 keV - 15 MeV range
by the GRB (Band) function with the following model parameters:
the low-energy photon index alpha = -1.01 (-0.30,+0.27),
the high energy photon index beta = -1.91 (-0.05,+0.04),
the peak energy Ep = 104 (-23,+39) keV,
chi2 = 111/97 dof.
All the quoted errors are estimated at the 90% confidence level.
All the presented results are preliminary.
GCN Circular 30539
Subject
GRB 210714A: Fermi GBM observation
Date
2021-07-28T15:20:05Z (4 years ago)
From
Elisabetta Bissaldi at INFN,Bari <elisabetta.bissaldi@ba.infn.it>
E. Bissaldi (Politecnico and INFN Bari)
reports on behalf of the Fermi GBM Team:
"At 07:56:33.25 UT on 14 July 2021, the Fermi Gamma-Ray Burst Monitor (GBM)
triggered and located GRB 210714A (trigger 647942198 / 210714331),
which was also detected by Konus-Wind (Frederiks et al. 2021, GCN 30467).
The on-ground calculated location, using the GBM trigger data, is
RA = 313.67, DEC = -51.59
(J2000 degrees, equivalent to 20 h 54 m, -51 d 35'),
with a statistical uncertainty
of 1 degree (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 109 degrees.
The GBM light curve consists of a bright, FRED-like pulse
with a duration (T90) of about 42 s (50-300 keV).
The time-averaged spectrum from T0 to T0+25 s is
best fit by a Band function with Epeak = 64 +/- 5 keV,
alpha = -0.68 +/- 0.09, and beta = -1.75 +/- 0.01.
The event fluence (10-1000 keV) in this time interval is
(4.67 +/- 0.15)E-05 erg/cm^2. The 1-sec peak photon flux measured
starting from T0+1.9 s in the 10-1000 keV band
is 48.9 +/- 0.7 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/"