A Westerbork survey of rich clusters of galaxies. V - Multi-frequency observations of the radio tail galaxy NGC 6034 in the Hercules cluster

Maps of the radio-brightness distribution at 5, 1.4, and 0.6 GHz of the wide-angle head-tail radio source 1601 plus 17W1 associated with the elliptical galaxy NGC 6034 in the Hercules cluster are presented. At 5 and 1.4 GHz the observations also provided polarization data. The spectral-index distributions between 0.6 and 1.4 GHz along the trails are given. The remarkable asymmetric source structure is discussed and interpreted as the result of an ejection not normal to the velocity of the galaxy. A simple ram-pressure model suffices to describe the observed differences in size, flux density, and spectral-index distribution of the two trails of the radio source as due to different expansion rates of the blobs in the two trails. A lower limit is derived for the product of the density and the temperature of the intracluster medium in this part of the Hercules cluster