We present sensitive, high resolution Very Long Baseline Array (VLBA) observations of the central 0.3′′ of PKS 2322−123 at 1.3 and 5 GHz. These observations reveal straight and symmetric jets emerging from both sides of an inverted spectrum core. The 21 cm line of atomic hydrogen is detected in absorption against the core and eastern jet with substantial opacities, but is not seen towards the equally strong western jet. Both a narrow (110 km s−1 FWHM) and a very broad (735 km s−1 FWHM) line are seen, although the very broad line is seen only against the core. Both lines are redshifted (∼220 ± 100 km s−1) with respect to the systemic velocity. The most likely explanation for the observed Hi kinematics are an atomic torus centered on the nucleus with considerable turbulence and inward streaming motions. The scale height of this torus is less than 20 pc. Though rare in flux limited samples of compact radio sources, symmetric parsec-scale structure appears nearly ubiquitous among radio galaxies with Hi absorption, probably because they are viewed more nearly edge-on through the torus. (Refer to PDF file for exact formulas).

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Also archived in: arXiv:astro-ph/9811343 v2 24 Nov 1998 GBT thanks STScI for hospitality during a visit in which this paper was written. This research has made use of the NASA/IPAC Extragalactic Database (NED) which is operated by the Jet Propulsion Laboratory, Caltech, under contract with NASA.ISSN:1538-4357 Note: imported from RIT’s Digital Media Library running on DSpace to RIT Scholar Works in February 2014.

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Department, Program, or Center

School of Physics and Astronomy (COS)


RIT – Main Campus