First results of the 74-MHz very large array-Pie town link. Hercules a at low frequencies

Abstract

We present the results of the first successful observations of the Pie Town link with the Very Large Array at 74 MHz on Hercules A. The improvement in resolution from 25 to 10 arcsec resolves the helical- and ring-like features seen at higher frequencies. We also present new high dynamic range images of this powerful radio galaxy at 325 MHz. Our low-frequency observations confirm the multiple outburst interpretation of the spectral index differences at high frequencies. A comparison between our radio and ROSAT X-ray data does not reveal any association between the X-ray emission from the cluster and the radio lobes. There are no extra regions of radio emission at 74 MHz. © 2005 RAS.