TITLE: GCN GRB OBSERVATION REPORT NUMBER: 5430 SUBJECT: GRB060807: Optical limiting magnitudes DATE: 06/08/09 18:03:12 GMT FROM: AAVSO GRB Network at AAVSO D. T. Durig (Cordell-Lorenz Observatory, University of the South) and S. Sposetti (Gnosca, Switzerland) report on behalf of the AAVSO International High Energy Network on optical observations of GRB060807 (GCN #5409, De Pasquale et al.): D. T. Durig reports the following unfiltered (CR) limiting magnitude: 2006 Aug 08, 03:41:45 UT, CR < 20.0 (15 hours, post-burst) S. Sposetti reports the following R-band limiting magnitude: 2006 Aug 08, 19:45:00 UT, R < 20 (29 hours, post-burst) Details of these observations follow at the end of this report. FITS images of these observations are available from the AAVSO at ftp://ftp.aavso.org/grb , and full details of these observations are available at the following URLs: Durig: http://www.aavso.org/pipermail/aavso-hen/2006-August/006238.html Sposetti: http://www.aavso.org/pipermail/aavso-hen/2006-August/006240.html The AAVSO thanks the Curry Foundation for their continued support of the AAVSO International High Energy Network. -------------------------- Observer: D. T. Durig ( CLW01 ) Report: Started 2 hours of 30 second unguided exposures and got a few thicker clouds near the end. So I added the first 150 good frames, total exposure 75 minutes. No OT observed, but there is a dim background variation at S/N~2 near reported position. Two accumulated hot pixels nearby center at 1 oclock position and one near top center of frame are artifacts. Gif image at http://arthur.sewanee.edu/obsv/view.php Bright moonlight made background very bad and limited depth of coverage. Observer: Stefano Sposetti Report: Observations begun at 19:45UT, aug 8th, about 29h later the Swift-BAT trigger, under good sky conditions affected by moonlight. A 90min stacked R-filtered image centred at 20:45UT doesn't show any OT brighter than 20mag (USNO A2.0 catalog).