Jet propagation and the asymmetries of CSS radio sources

¹ Physikalisches Institut, Universität zu Köln, Zülpicher Str. 77, 50937 Köln, Germany e-mail: sjk@rri.res.in
² Raman Research Institute, C. V. Raman Road, Bangalore 560080, India
³ Department of Physics & Astronomy, Georgia State University, PO Box 4106, Atlanta GA 30302-4106, USA
⁴ National Centre for Radio Astrophysics, TIFR, Post Bag No. 3, Ganeshkhind, Pune 411 007, India
⁵ E*trade Financial Corporation, 4500 Bohannon Drive, Menlo Park, CA 94025, USA

Received: 30 June 2004
Accepted: 10 November 2004

Abstract

As Compact Steep Spectrum radio sources have been shown to be more asymmetrical than larger sources of similar powers, there is a high probability that they interact with an asymmetric medium in the central regions of the host elliptical galaxy. We consider a simple analytical model of the propagation of radio jets through a reasonable asymmetric environment and show that they can yield the range of arm-length and luminosity asymmetries that have been observed. We then generalize this to allow for the effects of orientation, and quantify the substantial enhancements of the asymmetries that can be produced in this fashion. We present two-dimensional and three-dimensional simulations of jets propagating through multi-phase media and note that the results from the simulations are also broadly consistent with the observations.