TITLE: GCN GRB OBSERVATION REPORT NUMBER: 1468 SUBJECT: GRB020812(=H2257): A Long Burst Localized by HETE in Near-Real Time DATE: 02/08/12 15:10:59 GMT FROM: Don Lamb at U.Chicago G. Ricker, J-L Atteia, N. Kawai, D. Lamb, and S. Woosley on behalf of the HETE Science Team; J. Doty, R. Vanderspek, J. Villasenor, G. Crew,G. Monnelly, N. Butler, T. Cline, J.G. Jernigan, A. Levine, F. Martel, E. Morgan, G. Prigozhin, J. Braga, R. Manchanda, and G. Pizzichini, on behalf of the HETE Operations and HETE Optical-SXC Teams; 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; M. Boer, J-F Olive, J-P Dezalay, and K. Hurley on behalf of the HETE FREGATE Team; write: At 10:41:43.98 UTC (38503.98 s UT) on 12 Aug 2002, the HETE FREGATE and WXM instruments detected event H2257, a long GRB. The WXM flight localization was correct and was reported in a GCN Position Notice at 10:50:48 UT, 9 min 4 sec after the burst. Ground analysis produced a refined location, which was reported in a GCN Position Notice at 13:19:48 UT, 158 minutes after the burst. This location can be expressed as a 90% confidence rectangle that is 10 arcminutes by 25 arcminutes and is centered at RA = 20h 38m 48s, Dec = -05o 23' 34" (J2000). The corners of the location rectangle lie at the following J2000 coordinates: RA = 20h 39m 18s, Dec = -05o 35' 06" RA = 20h 38m 38s, Dec = -05o 36' 36" RA = 20h 38m 17s, Dec = -05o 12' 03" RA = 20h 38m 57s, Dec = -05o 10' 34". In the FREGATE 8-40 keV band, the burst had a duration of ~20 seconds. A total of 1741 net counts were detected in the 8-40 keV band during this interval, corresponding to a fluence of ~3.1 x 10-7 ergs cm-2. The peak flux averaged over 0.5 s was 4.9 x 10-8 ergs cm-2 s-1 (i.e., 1.6 x Crab flux). In the WXM 2-25 keV band, the burst had a duration of ~20 seconds. The WXM localization SNR was 6.3 in the X-detector and 8.3 in the Y-detector. Further information (including a light curve) for GRB020812 is provided at the following URL: http://space.mit.edu/HETE/Bursts/ This message is citable.