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Session 33 - Amateurs & Professionals: Collaborators in the New Age of Electronic Astronomy - II.
Oral session, Tuesday, June 10
North Main Hall C/D,

[33.04] Automated Astrometric and Photometric TASS Data Reduction Techniques

G. Gombert (Miami Valley Astronomical Society)

Since the fall of 1996 I have operated TASS Camera No. 1 in Dayton, Ohio, collecting data every clear night and also developing data analysis techniques to make automated astrometric and photometric measurements. I have often had the opportunity to compare results and refine my measurement techniques through frequent e-mail with Michael Richmond at Princeton University and Arne Henden at the U.S. Naval Observatory. Henden has contributed to the analysis by making measurements of several fields from data he has collected at USNO, to serve as a reference for measurements taken by various TASS cameras.

To compare results obtained at various TASS camera sites two specific fields were chosen for study:

Field A: RA = 12:30 - 12:45 Dec = 0 degrees Field B: RA = 08:45 - 09:00 Dec = 0 degrees

Field "A" is sparse at high galactic latitude; Field "B" is at a fairly low galactic latitude, is more crowded, much more of a challenge for automated data reduction methods.

To analyze the data from the Dayton TASS camera I used Emanual Burton's "SExtracotr" (or Source- Extractor) program to generate catalogs of detected objects. Burton, a PhD student at the Paris Observatory, developed Source-Extractor as a part of his thesis. Source-Extractor has been used reduce data from several astronomical survey projects, including data taken with the Hubble Space Telescope. (See "Deep Optical Galaxy Counts," ApJ, 20 August, 1995; "Lensing by Distant Clusters," ApJ, 20 December, 1995

My paper will focus will on the calibration method's used to make precise astrometric and photometric measurements from TASS images. Also, a comparison of the results achieved using the above technique with results obtained by Richmond and Henden using different methods to generate catalogs of objects from TASS images for the above mentioned "A" and "B" fields will be discussed.

Program listing for Tuesday