//////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3779 SUBJECT: GRB 050807: ROTSE-III Optical Limits DATE: 05/08/07 15:02:09 GMT FROM: Eli Rykoff at U of Michigan/ROTSE E.S. Rykoff, W. Rujopakarn, S.A. Yost, F. Yuan (U Mich) report on behalf of the ROTSE collaboration: ROTSE-IIIa, located at Siding Spring Observatory, Australia, responded to GRB 050807 (HETE trigger 3889). The initial response was delayed due to confusion with the different coordinates received in the first two GCN notices. Targeted observations of the updated GCN position (trigger 3889;3) began at 11:09:51.5 UT, 11.1 minutes after the burst, under excellent conditions. We took 10 5-sec, 10 20-sec and 35 60-sec exposures. These unfiltered images are calibrated relative to USNO A2.0. The final ground error box (trigger 3889;5) is entirely contained within the initial targeted observation. Comparison to the DSS (second epoch) reveals no new sources within the 3-sigma error box, for both single images and coadding into sets of 10. Individual images have limiting magnitudes ranging from 16.3-17.5; we set the following specific limits. start UT end UT t_exp(s) mlim t_start-tGRB(s) Coadd? -------------------------------------------------------------------- 11:09:51.5 11:12:7.4 136 17.7 666 Y 11:12:16.8 11:16:55.1 284 18.2 812 Y 11:17:9.9 11:28:34.3 684 18.5 1105 Y //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 3785 SUBJECT: GRB050807(=H3889): An X-Ray Rich GRB Localized by HETE DATE: 05/08/12 21:49:31 GMT FROM: Joel Villasenor at MIT M. Maetou, G. Ricker, J-L. Atteia, N. Kawai, D. Lamb, and S. Woosley, on behalf of the HETE Science Team; M. Arimoto, T. Donaghy, E. Fenimore, M. Galassi, C. Graziani, J. Kotoku, M. Matsuoka, Y. Nakagawa, T. Sakamoto, R. Sato, Y. Shirasaki, M. Suzuki, T. Tamagawa, K. Tanaka, 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: The HETE FREGATE, WXM, and SXC instruments detected GRB 050807 (=H3889) at 10:58:45 UT (39525 SOD) on 7 August 2005. The correct WXM flight localization was first reported in a GCN Notice issued at 10:59:19 UT, which was 34s after the burst trigger. Further WXM and SXC ground localizations were reported in a GCN Notice issued at 13:47:18 UT. The final WXM ground localization can be expressed as an 8 by 48 arcminute box (90% confidence) that is centered at WXM-Ground: RA = 20h 13m 27s, DEC = -36d 57' 06" (J2000) and defined by the corners: RA = 20h 13m 16s, DEC = -37d 21' 43" RA = 20h 12m 40s, DEC = -37d 18' 54" RA = 20h 13m 38s, DEC = -36d 32' 31" RA = 20h 14m 14s, DEC = -36d 35' 20". The SXC localization could only be localized along one axis, and hence yields a 3 by 32 arcminute box that is centered at SXC-Ground: RA = 20h 13m 27s, DEC = -36d 56' 12" (J2000) and defined by the corners: RA = 20h 13m 39s, DEC = -36d 40' 23" RA = 20h 13m 00s, DEC = -37d 11' 20" RA = 20h 13m 14s, DEC = -37d 12' 18" RA = 20h 13m 54s, DEC = -36d 40' 52". The burst has a duration T_90 of ~55 seconds in 6-40 keV and 6-80 keV, and a T_90 of ~28 seconds in 30-400 keV. Preliminary spectral analyses show the 2-30 keV fluence of GRB 050807 to be 1.3 x 10-6 ergs cm-2 and the 30-400 keV fluence to be 2.2 x 10-6 ergs cm-2. Thus, GRB 050807 is classified as an "X-ray-rich" GRB. A light curve, skymap, and spectral information for GRB 050807 are provided at the following URL: http://space.mit.edu/HETE/Bursts/GRB050807 This message may be cited.