The central engines of radio-quiet quasars

University of Oxford
Monthly Notices of the Royal Astronomical Society (Impact Factor: 5.11). 05/1998; 299(1). DOI: 10.1046/j.1365-8711.1998.01752.x
Source: arXiv


Two rival hypotheses have been proposed for the origin of the compact radio flux observed in radio-quiet quasars (RQQs). It has been suggested that the radio emission in these objects, typically some two or three orders of magnitude less powerful than in radio-loud quasars (RLQs), represents either emission from a circumnuclear starburst or is produced by radio jets with bulk kinetic powers 10^3 times lower than those of RLQs with similar luminosity ratios in other wavebands. We describe the results of high resolution (parsec-scale) radio-imaging observations of a sample of 12 RQQs using the Very Long Baseline Array (VLBA). We find strong evidence for jet-producing central engines in 8 members of our sample. Comment: 7 pages, 8 figures. Accepted for publication in MNRAS

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