////////////////////////////////////////////////////////////////////////
TITLE:   GCN CIRCULAR
NUMBER:  18864
SUBJECT: IPN Triangulation of GRB 160111A (short/hard)
DATE:    16/01/14 13:12:50 GMT
FROM:    Dmitry Svinkin at Ioffe Institute  <svinkin@mail.ioffe.ru>

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

K. Hurley, on behalf of the IPN,

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

A short-duration GRB 160111A has been detected by Konus-Wind, Swift 
(BAT), and INTEGRAL (SPI-ACS), so far, at about 26526 s UT (07:22:06). 
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:
    43.835 (02h 55m 20s) +34.176 (+34d 10' 34")
  Corners:
    45.937 (03h 03m 45s) +28.261 (+28d 15' 40")
    40.903 (02h 43m 37s) +39.971 (+39d 58' 17")
    41.650 (02h 46m 36s) +40.070 (+40d 04' 11")
    46.604 (03h 06m 25s) +28.319 (+28d 19' 08")
  ---------------------------------------------
The error box area is 7.1 sq. deg, and its maximum
dimension is 12.6 deg (the minimum one is 34.3 arcmin).
The Sun distance was 118 deg.

This box may be improved.

A triangulation map is posted at
http://www.ioffe.ru/LEA/GRBs/GRB160111_T26526/IPN/

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

////////////////////////////////////////////////////////////////////////
TITLE:   GCN CIRCULAR
NUMBER:  18865
SUBJECT: Konus-Wind observation of GRB 160111A
DATE:    16/01/14 14:05:13 GMT
FROM:    Dmitry Frederiks at Ioffe Institute  <fred@mail.ioffe.ru>

S. Golenetskii, R.Aptekar, D. Frederiks, 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-duration, hard-spectrum GRB 160111A
(IPN triangulation:  Golenetskii et al., GCN 18864)
triggered Konus-Wind at 26526.639 s UT (07:22:06.639).

The KW light curve shows a single pulse with a duration of ~0.3 s.
The emission is visible up to ~5 MeV.

The Konus-Wind light curve of this GRB is available at
http://www.ioffe.ru/LEA/GRBs/GRB160111_T26526/

As observed by Konus-Wind, the burst had a fluence
of 2.4(-0.8,+1.0)x10^-6 erg/cm2, and a 16-ms peak flux,
measured from T0, of 9.7(-3.1,+4.1)x10^-6 erg/cm2/s
(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 the cutoff power law with the following model parameters:
the photon index alpha = -0.06(-0.55,+0.84),
and the peak energy Ep = 682(-222,+367) keV,
chi2 = 15.6/19 dof.
Fitting this spectrum with the GRB (Band) function yields
the following model parameters:
the low-energy photon index alpha = -0.13 (-0.11,+0.08),
the high energy photon index beta < -2.35 (upper limit),
the peak energy Ep = 725 (-267, +321) keV,
chi2 = 15.7/18 dof.

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