Back

GRB 160702A

GCN Circular 19666

Subject

IPN Triangulation of GRB 160702A (short/hard)

Date

2016-07-08T20:18:06Z (9 years ago)

From

Anna Kozlova at Ioffe Institute <ann_kozlova@mail.ioffe.ru>

K. Hurley, on behalf of the IPN,

I. G. Mitrofanov, D. Golovin, M. L. Litvak, and A. B. Sanin,
on behalf of the HEND-Odyssey GRB team,

A. Kozlova, S. Golenetskii, R. Aptekar, D. Frederiks, D. Svinkin,
and T. Cline on behalf of the Konus-Wind team,

S. Barthelmy, J. Cummings, N. Gehrels, H. Krimm, and D. Palmer,
on behalf of the Swift-BAT team,

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

W. Boynton, C. Fellows, K. Harshman, H. Enos, and R. Starr,
on behalf of the GRS-Odyssey GRB team, report:

A short-duration GRB 160702A has been detected by Konus-Wind, INTEGRAL
(SPI-ACS), Mars-Odyssey(HEND), and Swift (BAT) at about 44544 s UT
(12:22:24). The burst was outside the coded field of view of the BAT.

We have triangulated it to a preliminary, 3 sigma error box whose
coordinates are:
 ---------------------------------------------
  RA(2000), deg                 Dec(2000), deg
 ---------------------------------------------
 Center:
  230.889 (15h 23m 33s)  +8.715 ( +8d 42' 54")
 Corners:
  231.265 (15h 25m 03s)  +9.181 ( +9d 10' 51")
  230.871 (15h 23m 29s)  +9.187 ( +9d 11' 15")
  230.515 (15h 22m 04s)  +8.245 ( +8d 14' 41")
  230.908 (15h 23m 38s)  +8.243 ( +8d 14' 33")
 ---------------------------------------------
The error box area is 1320 sq. arcsin, and its maximum
dimension is 1.194 deg (the minimum one is 22 arcmin).
The Sun distance was about 121 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB160702_T44544/IPN/

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

GCN Circular 19667

Subject

Konus-Wind observation of GRB 160702A (short/hard)

Date

2016-07-08T20:30:03Z (9 years ago)

From

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

D. Frederiks, S. Golenetskii, R.Aptekar, P. Oleynik, M. Ulanov,
D. Svinkin, A. Tsvetkova, A.Lysenko, A. Kozlova, and T. Cline,
on behalf of the Konus-Wind team, report:

The short GRB 160702A (IPN triangulation: Hurley et al., GCN 19666Loading...
 
 )
triggered Konus-Wind at T0=44544.054 s UT (12:22:24.054).

The light curve shows a short, hard pulse with a total duration
of ~200 ms.
The emission is seen up to ~5 MeV.

As observed by Konus-Wind, the burst had a fluence of
(2.5 �� 0.7)x10^-6 erg/cm2 and a 16-ms peak energy flux,
measured from T0-0.016, of (3.0 �� 0.4)x10^-5 erg/cm2
(both in the 20 keV - 10 MeV energy range).

The spectrum of the burst (measured from T0 to T0+0.128 s)
is best fit in the 20 keV - 10 MeV range by a cutoff power-law
(CPL) function with the following model parameters:
the photon index alpha = -0.28(-0.35,+0.48),
and the peak energy Ep = 782(-186,+308) keV,
chi2 = 32.3/31 dof.
Fitting this spectrum with the GRB (Band) function yields
the same alpha and Ep with only an upper limit on beta of -2.1,
chi2 = 31.9/30 dof.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160702_T44544/

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