Inversion symmetry of radio lobes in extragalactic sources

Abstract

The collimated beams of relativistic particles ejected from the central engines of extragalactic radio sources are traced out by means of the jet-like features of nonthermal radio emission which are observed to extend up to a few hundred kiloparsecs. These jets exhibit departures from linearity in a variety of ways. In some less luminous large radio galaxies, the jets show structures with a distinctive S-shaped bending (inversion symmetry) at distances of the order of 100 kpc from the galactic nucleus. We propose here that such a sharp bending can result from interaction of the relativistic beam fluid with faint, rotating shells similar to those seen around some nearby galaxies, and discuss the possible implications of this hypothesis.