GCN Circular 2839

GRB 041211(=H3622):  A Long GRB Localized by the HETE WXM and SXC

J-P Dezalay, 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, M. Matsuoka,
Y. Nakagawa, T. Sakamoto, R. Sato, Y. Shirasaki, M. Suzuki,
T. Tamagawa, Y. Urata, T. Yamazaki, Y. Yamamoto, and A. Yoshida, on
behalf of the HETE WXM Team;

N. Butler, G. Crew, J. Doty, A. Dullighan, G. Prigozhin, R. Vanderspek,
J. Villasenor, J. G. Jernigan, A. Levine, G. Azzibrouck, J. Braga,
R. Manchanda, and G. Pizzichini, on behalf of the HETE Operations and
HETE Optical-SXC Teams;

C. Barraud, M. Boer, J-F Olive, and K. Hurley, on behalf of the HETE
FREGATE Team;

report:

The HETE FREGATE, WXM, and SXC instruments detected GRB 041211 (=H3622)
at 11:31:47 UT (41507 SOD) on 11 December 2004.  No prompt location was
issued because of a lack of real-time spacecraft aspect information.
Ground analysis of the WXM data produced a location that was reported
in a GCN Notice issued at 12:51:48 UT.  This localization can be
expressed as a circle of 8 arcminutes radius (90% confidence) that is
centered at

WXM-Ground:  RA = 06h 43m 53s, DEC =  +20d 20' 17" (J2000).

The WXM location was further refined, resulting in a new location that
was reported in a GCN Notice at 11:31:47 UT.  This localization can be
expressed as a circle of 8.6 arcminutes radius (90% confidence) that
is centered at

WXM-Ground:  RA = 06h 43m 27s, DEC =  +20d 19' 58" (J2000).

Ground analysis of the SXC data resulted in a location that was issued
in the same Notice as the refined WXM localization.  This localization
can be expressed as a circle of 80 arcseconds radius that is centered
at

SXC-Ground:  RA = 06h 43m 12s, DEC =  +20d 23' 42" (J2000).

The burst has a duration > 100 s.  Preliminary spectral analyses show
the 2-30 keV fluence of GRB 041211 to be 2.4 x 10-6 ergs cm-2 and the
30-400 keV fluence to be 1.0 x 10-5 ergs cm-2.  Therefore GRB 041211 is
a classical "hard" GRB.  The empirical redshift indicator for this
burst gives a pseudoZ~3.0.

A light curve, skymap, and spectral information for GRB 041211 are
provided at the following URL:

http://space.mit.edu/HETE/Bursts/GRB041211

This message may be cited.