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Combining Optical and Radio Catalogs to Test Active Galactic Nuclei Unification

TYPEAstrophysics Seminar
Speaker:Prof. Paul J. Wiita
Affiliation:Department of Physics, The College of New Jersey
Date:03.01.2011
Time:13:30
Location:Lidow 620
Abstract:

After reviewing some key properties of AGN I will show how we can test the strength of the orientation based unification paradigm through the large numbers of radio quasars present in both the SDSS optical and FIRST radio surveys.  This sample of4714 radio quasars is over an order of magnitude larger than any such available heretofore and allows much stronger tests of correlations between line strengths and shapes and radio morphologies. Our conclusions include: radio quasars with unresolved core morphologies are redder than radio quiet quasars but other radio loud morphologies are not redder; the radio core-to-lobe ratio and the radio-to-optical ratio of the quasar core are both correlated and should act as orientation indicators; the rest equivalent widths of several lines correlate strongly and positively with the radio/optical ratio, but in contrast to earlier results, we don't see such EW correlations with the radio core/lobe ratio. However, this orientation indicator--equivalent width correlation is the opposite expected from commonly accepted orientation based theories.