TITLE: GCN CIRCULAR NUMBER: 831 SUBJECT: GRB000926 - Optical observations DATE: 00/10/05 04:04:33 GMT FROM: Christian Veillet at CFHT Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit GRB000926 - Optical observations The optical counterpart of GRB000926 has been observed using the CFH12K CCD mosaic camera at the prime focus of the 3.6-m CFH Telescope for the sixth night on Oct. 4.25 . The two images were with variable transparency and poor seeing conditions (0.9 to 1"). Star 2 (see GCN #830 and the web page referenced below) is used as a reference with R=20.36 for the following photometric data: Sept. 29.3075 21.23 0.03 30.3075 22.10 0.04 Oct. 1.2593 22.71 0.04 2.2626 23.13 0.08 3.2304 23.45 0.10 4.2500 23.73 0.15 T is in UTC days after Sept. 0 . R magnitudes are given with their uncertainty. A photometric check on stars 1 and 2 leads to mg1 - mg2 = 0.658 +/- 0.01 over the 6 nights of observations. A graph of the light curve in R from CFHT observations can be found at http://www.cfht.hawaii.edu/~veillet/grb.html as well as the last image of the OT vanishing in the background... We are done at CFHT with the observations of the OT itself. The observing time used for GRB000926 has been taken from allocated time to colleagues from Canada and Hawaii who are once more acknowledged, with for last night special thanks to M. Brodwin. The field will be imaged again when CFH12K will be on the telescope for a final photometric calibration before running the last analysis and publishing the data. This run has been more hectic than the one on GRB000301C. Sorry for that... Aloha! This message may be cited. -- ************************************************************ Dr. Christian Veillet, CFHT Senior Resident Astronomer Phone: (808) 885-3161 http://www.cfht.hawaii.edu/~veillet/ ************************************************************