| Circular_text |
TITLE: GCN CIRCULAR
NUMBER: 32206
SUBJECT: Konus-Wind detection of GRB 220613A
DATE: 22/06/17 15:58:15 GMT
FROM: Anna Ridnaia at Ioffe Institute
A.Ridnaia, D. Frederiks, A.Lysenko, D. Svinkin,
A. Tsvetkova, M. Ulanov, and T. Cline,
on behalf of the Konus-Wind team, report:
The long-duration GRB 220613A
(IPN triangulation: Kozyrev et al., GCN Circ. 32205)
triggered Konus-Wind at T0=73416.994 s UT (20:23:36.994).
The burst light curve contains two major emission episodes.
The first one, lasting from ~T0-6 s to ~T0+15 s, and
the second episode, from ~T0+89 s to ~T0+133 s.
The total burst duration was ~173 s.
The emission is seen up to ~10 MeV.
The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB220613_T73416/
As observed by Konus-Wind, the burst
had a fluence of 2.61(-0.35,+0.34)x10^-4 erg/cm2,
and a 64-ms peak flux, measured from T0+6.288 s,
of 3.06(-0.48,+0.48)x10^-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).
The time-averaged spectrum of the burst
(measured from T0 to T0+170.496 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.99(-0.12,+0.14),
the high energy photon index beta = -1.88(-0.30,+0.15),
the peak energy Ep = 719(-199,+323) keV
(chi2 = 109/86 dof).
The spectrum near the maximum count rate
(measured from T0+5.888 to T0+7.680 s)
is best fit in the 20 keV - 10 MeV range
by the GRB (Band) model with the following parameters:
the low-energy photon index alpha = -0.78(-0.08,+0.09),
the high energy photon index beta = -2.32(-0.43,+0.23),
the peak energy Ep = 1106(-187,+221) keV
(chi2 = 73/71 dof).
All the quoted errors are at the 90% confidence level.
All the quoted values are preliminary.
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