AAVSO: American Association of Variable Star Observers
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CCD Photometry and Astrometry at Colgate University (Abstract)

Volume 21 number 1 (1992)

Thomas J. Balonek
Colgate University, Department of Physics and Astronomy, Hamilton, NY

Abstract

(Abstract only) A Ferson 16-inch multi-access Cassegrain/Newtonian telescope at the Colgate University Foggy Bottom Observatory has been used with two different Photometrics CCD Camera systems to obtain over 11,000 images during a three-year period in studies of the BVRI variability of quasars, active galactic nuclei, and extragalactic supernovae. Projects which were selected take advantage of the nearly unlimited telescope time available at the on-campus observatory. This ready access provides for good time resolution and long-term coverage of variability in several optical colors. Photometric accuracy of 1-2% is regularly obtained for 15th magnitude objects. Results of these studies are presented. Several asteroids have been serendipituously discovered in images obtained during the course of the photometric projects. Astrometric positions (with accuracy 1") of these and other asteroids have been obtained using reference star positions form the Hubble Space Telescope Guide Star Catlog (GSC) CD-ROM. The CCD systems used are: a Photometrics PM3000 system which includes a liquid nitrogen-cooled Thomsen 7882 chip controlled by a Heurikon workstation; a Photometrics software on the Heurikon work station and IRAF on a DECstation 5000/200 workstation.