3C 129 at 90 Centimeters: Evidence for a Radio Relic?

Abstract

We present a new wide-field map of the radio galaxy 3C 129 and its companion galaxy 3C 129.1 at λ=90 cm. We see a distinct steep-spectrum feature near the head of 3C 129, extending in a direction perpendicular to the radio tails. We propose that this Crosspiece might consist of fossil radio plasma, which has been reenergized by the compression of the bow shock of the supersonically moving galaxy 3C 129. One possible origin of the fossil radio plasma could be the tail of a nearby head-tail radio galaxy. We discuss the implications of and give testable predictions for this scenario.