1999/11/24 by E. Ros, J. A. Zensus, A. P. Lobanov
Physics and Astronomy · #astro-ph
published as Astronomy & Astrophysics, 354, 55-66 (2000) · 13 pages, 13 figures, Accepted for publication in Astronomy & Astrophysics, main Journal
arxiv created 1999/11/24 · arxiv updated 2009/12/01
We have studied the parsec-scale structure of the quasar 3C345 at λλ1.3, 2, 3.6, and 6 cm, using total intensity and linear polarization images from 3 epochs of VLBA observations made in 1995.84, 1996.41, and 1996.81. The images show an unresolved "core" and a radio jet extending over distances up to 25 milliarcseconds. At 1.3 and 2 cm, images of the linearly polarized emission reveal an alignment of the electric vector with the extremely curved inner section of the jet. At 6 cm, the jet shows strong fractional polarization (m~15%), with the electric vector being oriented perpendicular to the jet. This is consistent with the existence of a transition from the shock-dominated to the plasma interaction-dominated emission regimes in the jet, occurring at a distance of ~1.5 milliarcseconds from the "core".