GCN Circular 30048
Subject
Konus-Wind detection of GRB 210514A
Event
Date
2021-05-18T18:03:52Z (5 years ago)
From
Anna Ridnaia at Ioffe Institute <ridnaia@mail.ioffe.ru>
A. Ridnaia, D. Frederiks, S. Golenetskii, A. Lysenko, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline, report:
The long-duration GRB 210514A
(Swift-BAT detection: Ambrosi et al., GCN 30008;
Lien & Ambrosi, GCN 30009; Markwardt et al., GCN 30018;
CALET-CGBM detection: Sakamoto et al., GCN 30035)
triggered Konus-Wind at T0=66225.021 s UT (18:23:45.021).
The burst light curve shows a multipeaked structure
started at ~T0-0.3 s with a total duration of ~74.2 s.
The emission is seen up to ~2 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB210514_T66225/
As observed by Konus-Wind, the burst
had a fluence of 1.97(-0.43,+0.56)x10^-5 erg/cm2,
and a 64-ms peak flux, measured from T0+1.168 s,
of 6.70(-3.12,+3.85)x10^-6 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst
(measured from T0 to T0+49.408 s)
is best fit in the 20 keV - 2 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.38(-0.40,+0.88),
the high energy photon index beta = -2.27(-0.42,+0.23),
the peak energy Ep = 118(-24,+40) keV
(chi2 = 66/55 dof).
The spectrum near the maximum count rate
(measured from T0 to T0+8.448 s)
is best fit in the 20 keV - 2 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.42(-0.53,+1.22),
the high energy photon index beta = -2.26(2.26,+0.39),
the peak energy Ep = 204(-82,+113) keV
(chi2 = 57/55 dof).
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.