GCN Circular 4550

GRB 060121:  A bright short/hard GRB localized by HETE-2 WXM


M. Arimoto, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley,
on behalf of the HETE Science Team;
 
T. Donaghy, E. Fenimore, M. Galassi, C. Graziani, N. Ishikawa,
A. Kobayashi, J. Kotoku, M. Maetou, M. Matsuoka, Y. Nakagawa,
T. Sakamoto, R. Sato, T. Shimokawabe, Y. Shirasaki, S. Sugita,
M. Suzuki, T. Tamagawa, K. Tanaka, and A. Yoshida, on behalf of the
HETE WXM Team;
 
N. Butler, G. Crew, J. Doty, G. Prigozhin, R. Vanderspek,
J. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga,
R. Manchanda, G. Pizzichini, and S. Gunasekera, on behalf of the HETE
Operations and HETE Optical-SXC Teams;
 
M. Boer, J-F Olive, J-P Dezalay, and K. Hurley, on behalf of the HETE
FREGATE Team;
 
report:

At 22:24:54.5 UTC (80694.5 SOD) on 21 January 2006 the HETE FREGATE,
WXM, and SXC instruments detected event H4010, a bright short/hard GRB.

The WXM flight location was distributed in a GCN Notice at 22:25:08 
UTC, 13 seconds after the start of the burst.  Ground analysis of the
WXM data yields a best-fit location

R.A. = +09h 10m 04s ; Dec. = +45d 41' 24" (J2000),

with a 90% confidence error radius of 8 arcminutes.

The T90 duration of the burst is approximately 2 s in the FREGATE
80-400 keV energy band.

Further analyses are in progress.  Further information about this burst
will be available at the following URL:

http://space.mit.edu/HETE/Bursts/GRB060121