//////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2966 SUBJECT: GRB 050123(=H3666): A GRB Localized in Real Time by HETE DATE: 05/01/23 12:49:32 GMT FROM: Roland Vanderspek at MIT GRB 050123 (=H3666): A GRB Localized in Real Time by HETE K. Hurley, G. Ricker, J-L. Atteia, N. Kawai, 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; R. Vanderspek, N. Butler, G. Crew, J. Doty, G. Prigozhin, 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, and J-P Dezalay, on behalf of the HETE FREGATE Team; report: HETE detected GRB 050123 at 10:22:54 (37374 s SOD) on 23 January 2005. GRB 050123 consists of a single peak of ~10 seconds duration and is clearly seen in both the 7-30 keV and 30-400 keV bands. The burst was localized in flight to coordinates RA = 10h 31m 33.5s, Dec = -11d 34m 15s (J2000) with a radius of 14'. The first flight localization was distributed 22 seconds after the burst trigger. Ground analyses of the burst allow us to refine the error box of GRB 050123 to a box with corners RA = 10h 31m 49.2s Dec = -11d 41m 31s (J2000) RA = 10h 30m 48.7s Dec = -11d 37m 01s RA = 10h 31m 23.2s Dec = -11d 15m 25s RA = 10h 32m 23.7s Dec = -11d 20m 02s Preliminary spectral analysis of the burst give a 30-400 keV fluence of 2e-6 erg/cm2 and an Epeak of 80 keV. Details of this burst may be found at http://space.mit.edu/HETE/Bursts/GRB050123 This message may be cited. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2967 SUBJECT: GRB050123: P60 Observations DATE: 05/01/23 13:06:09 GMT FROM: Derek Fox at CIT Derek B. Fox (Caltech) reports on behalf of the Caltech-NRAO-Carnegie GRB collaboration: "We have observed the WXM localization region of GRB050123 (=H3666; Hurley et al., GCN 2966) with the robotic Palomar 60-inch telescope, in a series of R-band exposures beginning at 10:36:15 UT. A mosaic of our first exposure set reaches exposures of 30s to 120s over >95% of the final 15' x 24' error box, at a mean epoch of 11:02 UT. Comparison of this mosaic to the Digitized Sky Survey reveals no new sources to a limit of R>~19 mag. Further analysis of these and later images is ongoing." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2968 SUBJECT: GRB 050123: KAIT observations DATE: 05/01/24 04:32:25 GMT FROM: Weidong Li at UC Berkeley KAIT/LOSS W. Li, A. V. Filippenko, R. Chornock, and S. Jha (University of California, Berkeley) report: "The Katzman Automatic Imaging Telescope (KAIT; see Li et al. 2003, PASP, 115, 844) at Lick Observatory robotically observed GRB 050123 (HETE Trigger #3666; Hurley et al., GCN 2966). Three batches of unfiltered images were taken, covering a 12.6' x 12.6' field centered on R.A. = 10h30m31s, DEC = -11d 52'17" (J2000) (from 10:23:38 UT to 10:54:37 UT), R.A. = 10h31m33s, DEC = -11d 34'14" (J2000) (from 10:58:31 UT to 11:58:53 UT), and R.A. = 10h31m26s, DEC = -11d 28'28" (J2000) (from 12:11:26 UT to 12:32:26 UT), respectively. We detected no new objects in our observations when compared to the DSS II images. The following 3-sigma limiting magnitudes are derived (calibrated with USNO-A2.0 red magnitudes) from selected images: R~17.5 mag for a 3 x 5 s grid image (6.6' x 6.6') started at 10:23:38 UT (44 s after the burst), R~19.0 for a 60 s image (6.6' x 6.6') started at 10:30:36 UT (462 s after the burst), and R~20.0 for a 2 x 2 mosaic 120 s image (12.6' x 12.6') centered at 10:51:57 UT (1743 s after the burst)." //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2969 SUBJECT: GRB050123,optical observation DATE: 05/01/24 08:54:57 GMT FROM: Shouta Maeno at U.of Miyazaki S.Maeno,E.Sonoda,Y.Matsuo,M.Yamauchi (University of Miyazaki) "We have observed the field covering the error box of GRB 050123 (HETE trigger 3666;trigger time 10:22:53 UT) with the unfiltered CCD camera on the 30-cm telescope at University of Miyazaki. The observation was started 17:05:26 UT on Jan.23. Observed field of view is 43 arcmin centerd on R.A.=10h 31m 58s Dec=-11d 26' 00" After co-adding a set of 5 images of 30 sec exposures, we have compared with the USNO A2.0 catalog. Preliminary analysis shows there is no new source brighter than 17.4 mag. //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2970 SUBJECT: GRB050123: optical limit 1.8h before GRB DATE: 05/01/24 09:33:35 GMT FROM: Grzegorz Wrochna at Soltan Inst.for Nuclear Studies M.Cwiok, K.Krupska, K.Kwiecinska, L.Mankiewicz, K.Nawrocki, B.Pilecki, L.W.Piotrowski, G.Pojmanski, M.Sokolowski, D.Szczygiel, G.Wrochna, on behalf of "Pi of the Sky / ASAS" collaboration http://grb.fuw.edu.pl The GRB 050123 (GCN 2966) error box was observed by "Pi of the Sky" apparatus at Las Campanas Observatory at 8:35 UT, i.e. 1h 48min before the GRB. 3 exposures, 10s each, have been taken by 2 cameras. No new object has been found within the HETE error box. The limiting magnitude on 3 coadded frames is 12m (unfiltered). //////////////////////////////////////////////////////////////////////// TITLE: GCN GRB OBSERVATION REPORT NUMBER: 2971 SUBJECT: GRB 050123 : I-band follow-up observation DATE: 05/01/24 12:39:42 GMT FROM: Kuiyun Huang at IANCU GRB 050123 : I-band follow-up observation Z.Y. Lin, K.Y. Huang, W.H. Ip (NCU), Y. Urata, T. Tamagawa (RIKEN), Y. Qiu (BAO), Y.Q. Lou(THCA) on behalf of the East Asian collaboration report: "We have observed the GRB 050123 error range reported by Hurley et al.(GCN 2966) using Lulin 1-m telescope at Taiwan. Our observations with I band started from 15.87 UT to 16.72 UT (~5.49 to 5.79 hours after the burst). These images cover 70 % error region of GRB 050123 (Hurley et al., GCN 2966). Comparing DSS-II image, no candidate was detected in our I band images. The average of limiting magnitude is about 19 (S/N=3, compared with USNO-B1 I magnitude)." This message may be cited.