G. Ricker, D. Lamb, and S. Woosley on behalf of the HETE Science Team;
R. Vanderspek, G. Crew, J. Doty, G. Monnelly, J. Villasenor; N.
Butler, T. Cline, J.G. Jernigan, A. Levine, F. Martel, G. Pizzichini,
and G. Prigozhin, on behalf of the HETE Operations and HETE
N. Kawai, M. Matsuoka, Y. Shirasaki, T. Tamagawa, A. Yoshida, E.
Fenimore, M. Galassi, and C. Graziani, on behalf of the HETE WXM
J-L Atteia, M. Boer, J-F Olive, J-P Dezalay, and K. Hurley on behalf
of the HETE FREGATE Team;
On 26 March 2001 at 08:33:12 UTC (=30792s UT), a soft spectrum, high
energy transient at high galactic latitude was detected and localized
(NB: This is the second GRB detected by HETE on 26 March 2001.)
Both the WXM and the FREGATE instruments detected the event. The
burst triggered FREGATE in the 6-120 keV band, at the 160ms timescale.
The preliminary coordinates of the burst are R.A. = 11h24m23.36s,
Dec. = -11o09'57", derived from combining data from the WXM and
Boresighted Optical Cameras. The statistical error radius in the WXM
localization is 18 arcmin (90% confidence). In addition, we estimate
a systematic error radius at present of 10 arcmin about this
location. The spacecraft aspect was known to an accuracy of +/- 30
arcsec (95% confidence) from the optical cameras, and will be
The peak flux seen with FREGATE (6-30 keV) was ~4 Crab; with WXM
(2-25 keV), ~2 Crab. The burst duration was about 4 seconds.
The high galactic latitude of the source, well away from the Galactic
Bulge, and the shape of its spectrum suggest that it is a gamma-ray
burst similar to those reported for "X-ray rich" GRBs by Heise et al
(2001) from BeppoSAX observations.
Follow-up observations of this unusual transient are encouraged.
Additional information on the GRB010326B (including light curves), as
well as for the HETE mission, is available at:
HETE=High Energy Transient Explorer
FREGATE=French Gamma Ray Telescope
WXM=Wide Field X-ray Monitor
SXC=Soft X-ray Camera
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