TITLE: GCN GRB OBSERVATION REPORT NUMBER: 844 SUBJECT: GRB000926 - Amateur Optical Observations DATE: 00/10/11 00:54:03 GMT FROM: AAVSO GRB Network at AAVSO Janet A. Mattei, AAVSO Director, reports: On the evening of September 28 UT, in response to an alert on the AAVSO's GRB mailing list, Joe Dellinger, Fort Bend Astronomy Club (FBAC), Texas, took a sequence of unfiltered CCD images of the GRB000926 field. He used the FBAC's 46 cm reflector at the Houston Museum of Natural Science's George Observatory, and an SBIG ST-9e camera on generous loan from Rice University. He could not see any optical transients on individual four-minute images when comparing them with a DSS-derived finder chart. Fellow FBAC member Bill Dillon combined the best seven of Joe's four-minute images into an equivalent 28 minute image. The combined image's UT mid-point time was 03:16:16. From positions and annotated images reported by professional astronomers, he realized that the OT had been imaged, near the threshold of detection. Using Astrometrica and the USNO-A2.0 catalog, the OT's position was measured at: RA 17h 04m 09.76s, DEC +51d 47' 10.6" with a magnitude of roughly 19.1. On the evening of October 3 UT, Randy Pepper and Bill Dillon did follow-up imaging of the GRB000926 field using the same telescope and camera. The OT had faded below detectability on a image made by combining 31 one-minute exposures. Joe, Bill, and Randy are all members of the FBAC's Gamma Ray Burst Extended Team, formed as the result of the NASA-MSFC/AAVSO High Energy Astrophysics Workshop held this April in Huntsville, Alabama. More information and imagery associated with this detection are available at http://www.geocities.com/amicustellarum/grb/grb000926.html This message may be cited.