TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1565 SUBJECT: GRB021004(=H2380): A Long GRB Localized by HETE in Near-Real Time DATE: 02/10/04 15:29:04 GMT FROM: Don Lamb at U.Chicago Y. Shirasaki, C. Graziani, M. Matsuoka, T. Tamagawa, K. Torii, T. Sakamoto, A. Yoshida, E. Fenimore, M. Galassi, T. Tavenner, and T. Donaghy, on behalf of the HETE WXM Team; G. Ricker, J-L Atteia, N. Kawai, D. Lamb, and S. Woosley on behalf of the HETE Science Team; J. Villasenor, R. Vanderspek, J. Doty, G. Crew, G. Monnelly, N. Butler, T. Cline, J.G. Jernigan, A. Levine, F. Martel, E. Morgan, G. Prigozhin, G. Azzibrouck, J. Braga, R. Manchanda, and G. Pizzichini, 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; write: At 12:06:13.57 UTC (43573.57 s UT) on 4 Oct 2002, the HETE FREGATE, WXM, and SXC instruments detected event H2380, a long GRB. The WXM flight localization was correct and was reported in a GCN Position Notice at 12:07:02 UT, 49 sec after the beginning of the burst. Ground analysis of the WXM data for the burst produced a refined location, which was reported in a GCN Position Notice at 13:19:54 UT, 73 minutes after the burst. The WXM localization SNR was 14. The WXM location can be expressed as a 90% confidence circle that is 10 arcminutes in radius and is centered at RA = 00h 26m 47s, Dec = +18d 59' 13" (J2000). Ground analysis of the SXC data for the burst produced a further refinement in the location, which was reported in a GCN Position Notice at 14:39:51 UT, 154 minutes after the burst. The SXC localization SNR was 9. The SXC location can be expressed as a 90% confidence circle that is 2 arcminutes in radius and is centered at RA = 00h 26m 57s, Dec = +18d 55' 44" (J2000). The SXC localization may be improved. In the FREGATE 8-40 keV band, the burst had a duration of ~100 seconds. In the WXM 2-25 keV band, the burst also had a duration of ~100 seconds. A light curve for GRB021004 is provided at the following URL: http://space.mit.edu/HETE/Bursts/ This message is citable.