TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3013 SUBJECT: GRB050209 (=U11568): A Long GRB Detected by HETE DATE: 05/02/09 06:23:53 GMT FROM: George Ricker at MIT GRB050209 (=U11568): A Long GRB Detected by HETE N. Kawai, G. Ricker, J-L. Atteia, 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, 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; M. Boer, J-F Olive, J-P Dezalay, and K. Hurley, on behalf of the HETE FREGATE Team; report that: Post-processing analysis of HETE data has revealed the presence of GRB 050209, an untriggered GRB (=U11568) detected as HETE was entering the SAA. The burst was detected at 01:31:41 UT and had a duration of approximately 40 seconds. The GRB has been localized to a circle of radius 7' (90% confidence) centered at: RA = 08h 26m 09s, DEC = +19d 41m 02s (J2000). Light curves in four spectral bands and a skymap for GRB 050209 are provided at the following URL: http://space.mit.edu/HETE/Bursts/GRB050209 Because of the proximity of the SAA, extraction of spectral data requires manual processing, and will be provided in a follow-up GCN Circular. This message may be cited.