[vsnet-grb-info 3019] Bright short hard GRB 060303: IPN localization and Konus spectrum

[GCN Circulars]

TITLE:   GCN GRB OBSERVATION REPORT
NUMBER:  4856
SUBJECT: Bright short hard GRB 060303: IPN localization and Konus spectrum
DATE:    06/03/10 19:19:30 GMT
FROM:    Valentin Pal'shin at Ioffe Inst  <val at mail.ioffe.ru>

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

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

A. von Kienlin, G. Lichti, A. Rau, D. Gotz, and S. Mereghetti,
on behalf of the INTEGRAL GRB team,

K. Hurley, D. M. Smith, R. P. Lin, J. McTiernan, R. Schwartz, C. Wigger, 
W. Hajdas, and A. Zehnder, on behalf of the RHESSI GRB team,

and K.Yamaoka, M.Ohno, Y.Fukazawa, T.Takahashi, M.Tashiro, Y. Terada,
T.Murakami, and K.Makishima on behalf of the Suzaku WAM team

report:

Konus-Wind, INTEGRAL-SPI-ACS, RHESSI, Suzaku-WAM, and Swift-BAT observed 
a bright short hard GRB at about 22:42:47 UT on March 3.
The burst was outside of the field of view of Swift-BAT, so it was not
imaged. Ulysses was off, and Odyssey did not observe this event.

We have derived a triangulation annulus centered at
RA(2000), Dec(2000) = 42.325 deg,  +16.869 deg,
whose radius is 73.266 ±0.173 deg (3 sigma).
Combining the all available data we have triangulated the GRB to
the section of this annulus between
RA(2000), Dec(2000)= 221, +26 and 230, +71 degrees.

As observed by Konus-Wind it had a duration of ~0.6 s,
fluence 1.16(-0.20,+0.19)x10^-5 erg/cm2,
and the 16-ms peak flux measured from T0+0.206 s
4.27(-1.11,+1.08)x10^-5  erg/cm2/s
(both in the 20 keV - 5 MeV energy range).

The spectrum integrated over the most intense part of the burst
(accumulated from T0 to T0+0.256 s)
is well fitted in the 20 keV - 5 MeV range
by GRBM (Band) model for which:
the low-energy photon index is alpha = -0.35(-0.16, +0.18),
the high energy photon index beta = -2.51(-2.32, +0.48),
the break E0 = 702(-232, +256) keV (chi2 = 52/41 dof).
The peak energy Epeak = 1158(-281, +305) keV.

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