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GRB 120617A

GCN Circular 13370

Subject

IPN Triangulation of GRB 120617A (short/intense)

Date

2012-06-18T20:28:42Z (13 years ago)

From

Dmitry Svinkin at Ioffe Institute <svinkin@mail.ioffe.ru>

S. Golenetskii, R. Aptekar, E. Mazets, V. Pal'shin, D. Frederiks,
D. Svinkin, and T. Cline on behalf of the Konus-Wind team,

K. Hurley, and J. Goldsten, on behalf of the MESSENGER GRNS GRB team,

and

A. von Kienlin, X. Zhang, A. Rau, V. Savchenko, E. Bozzo, and C.
Ferrigno, on behalf of the INTEGRAL SPI-ACS GRB team, report:

The bright, short-duration GRB 120617A has been observed by INTEGRAL 
(SPI-ACS), Konus-Wind, and MESSENGER (GRNS), so far, at about 54171 s UT 
(15:02:51).

We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
    ---------------------------------------------
     RA(2000), deg                 Dec(2000), deg
    ---------------------------------------------
    Center:
      22.309 (01h 29m 14s) +33.804 (+33d 48' 14")
    Corners:
      22.485 (01h 29m 57s) +33.057 (+33d 03' 25")
      22.035 (01h 28m 08s) +34.123 (+34d 07' 23")
      22.140 (01h 28m 34s) +34.534 (+34d 32' 02")
      22.583 (01h 30m 20s) +33.482 (+33d 28' 55")
    ---------------------------------------------
The error box area is 881 sq. arcmin, and its maximum
dimension is 90 arcmin (the minimum one is 25 arcmin).

This box may be improved.

The time history and spectrum will be given in a forthcoming GCN Circular.

GCN Circular 13371

Subject

Konus-Wind observation of GRB 120617A

Date

2012-06-19T12:24:29Z (13 years ago)

From

Dmitry Frederiks at Ioffe Institute <fred@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, D. Frederiks, E. Mazets, V. Pal'shin,
P. Oleynik, M. Ulanov, D. Svinkin, and T. Cline on behalf
of the Konus-Wind team, report:

The short-duration intense GRB 120617A
(IPN localization: Golenetskii at al., GCN 13370Loading...
 
 )
triggered Konus-Wind at T0=54167.025s UT (15:02:47.025)

The light curve shows two pulses,
a total duration of the burst is ~0.5 s.
The emission is seen up to ~4 MeV.
A spectral lag between G2(80-300 keV) and G1(20-80 keV)
instrument's light curves is estimated to 28 +/- 4 ms (1 sigma).

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB120617_T54167/

As observed by Konus-Wind the burst
had a fluence of 2.1(-0.2,+0.2)x10-6 erg/cm2,
and a 16-ms peak flux, measured from T0+0.256 s,
of 1.5(-0.3,+0.4)x10-5 erg/cm2/s
(both in the 20 keV - 10 MeV energy range).

The spectrum of the burst (measured from T0 to T0+0.256 s)
is well fit in the 20 keV - 10 MeV range
by a power law with exponential cutoff model, for which
alpha = -0.95 (-0.4, +0.5),
and Ep = 180(-40, +70) keV,
chi2 = 12.6/22 dof.

All the quoted results are preliminary.
All the quoted errors are at the 90% confidence level.