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B. G. Piner (Whittier College), A. L. Fey (U. S. Naval Observatory), J. Milne, M. Mahmud (Whittier College)
We present first results in a project to study the parsec-scale jet kinematics of sources in the U.S. Naval Observatory's Radio Reference Frame Image Database (RRFID). The RRFID consists of VLBA snapshot observations at 8 and 2 GHz, and is intended to allow monitoring of these sources for variability or structural changes so they can be evaluated for continued suitability as radio reference frame objects. The Image Database currently contains 2732 images of 446 sources from 1994 to 1998, with some source having images at as many as 18 epochs.
Here we present measurements of the apparent jet speeds for the 23 best-observed sources in the database, or all of those which have observations at 14 or more epochs. Together these 23 sources account for roughly 10% of the images in the database, and include the well-known sources OJ 287 and 4C 39.25, as well as several gamma-ray blazars. Measurement of apparent jet speeds from the RRFID will constrain jet Lorentz factors and viewing angles for this source population, and provide valuable statistical information that can be compared with the results of other large VLBI kinematic surveys such as the Caltech-Jodrell Bank and VLBA 2cm Survey.
If you would like more information about this abstract, please follow the link to http://rorf.usno.navy.mil/RRFID/. This link was provided by the author. When you follow it, you will leave the Web site for this meeting; to return, you should use the Back comand on your browser.
The author(s) of this abstract have provided an email address for comments about the abstract: gpiner@whittier.edu
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Bulletin of the American Astronomical Society, 34
© 2002. The American Astronomical Soceity.