Probing the ionized ISM of the CSS quasar 3C 277.1

I. Observations

¹ National Radio Astronomy Observatory, 520 Edgemont Road, Charlottesville, VA 22903-2475, USA e-mail: bcotton@nrao.edu
² Istituto di Radioastronomia – INAF, via P. Gobetti 101, 40129 Bologna, Italy
³ Dipartimento di Fisica, Universitá di Bologna, via Irnerio 46, 40126 Bologna, Italy
⁴ Australian National University, Mt. Stromlo Observatory, Cotter Rd., Weston, ACT 2611, Australia
⁵ NRAL-Jodrell Bank, University of Manchester, Macclesfield Cheshire, SK11 9DL, UK

Received: 11 October 2005
Accepted: 3 November 2005

Abstract

We present new multi-wavelength high resolution VLA polarimetric images of the CSS quasar 3C 277.1 and analyze them with older Merlin and HST [OIII] images. These observations were made to test the hypothesis that the [OIII] emission as well as the long wavelength radio opacity arise in shocks that the quasar jet induces in the ISM. The multi-wavelength radio polarimetric images allow the study of the intervening magnetized plasma using Faraday effects. The HST [OIII] image potentially reveals regions of shock that have cooled sufficiently to radiate. We find no compelling evidence that the jet is directly responsible for the majority of the [OIII] emission or that there is significant dense shocked material in the immediate vicinity of most of the jet. There is evidence for jet-induced shocks on the northern edge of the eastern lobe. We find a spectral age of the radio source of ∼ yr giving advance speeds of the lobes of 0.15 c and 0.06 c for the western and eastern lobes. The strong Faraday effects appear to be confined within the inner 3 kpc as does the [OIII] emission.