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The Central Parsecs of the Bright Quasar PKS 1921 - 293

Z. -Q. Shen·J. M. Moran·K. I. Kellermann
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Abstract

We report on a VLBA imaging study of the nearby bright southern blazar PKS 1921 - 293 (OV - 236). High resolution VLBA observations, made at four frequencies (5, 12, 15, and 43 GHz) over the period 1994 - 2000, have revealed a strongly curved jet extending out to about 50 parsecs from the presumed central engine. Two epoch VLBA observations, each simultaneously carried out at both 5 and 43 GHz, show a large position angle difference of 51 - 67 degrees between the jet emission at 5 and 43 GHz. Although the core of PKS 1921 - 293 has one of the highest brightness temperatures measured in any compact radio source, unlike other bright blazars it is not a source of gamma-ray emission. However, there is evidence in these images for superluminal motion within the central region (a few parsecs from the core) and within the north-east diffuse emission region. In all six-epoch 43 GHz images, two equally compact bright components within the central parsec are seen.

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Z. -Q. Shen, J. M. Moran, K. I. Kellermann. 2002-09-12. The Central Parsecs of the Bright Quasar PKS 1921 - 293. https://arxiv.org/abs/astro-ph/0209234

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