The Impact of the Early Stages of Radio Source Evolution on the ISM of the Host Galaxies
Abstract
The study of both neutral and ionised gas in young radio sources is providing key information on the effect the radio plasma has on the ISM of these objects. We present results obtained for the compact radio sources PKS1549-79, 4C12.50 and PKS1814-63 and for the intermediate-size radio galaxy 3C459. At least in the first two, low ionisation optical emission lines and HI absorption appear to be associated with the extended, but relatively quiescent, dusty cocoon surrounding the nucleus. The [OIII] lines are, on the other hand, mostly associated with the region of interaction between the radio plasma and the ISM, indicating a fast outflow from the centre. A case of fast outflow (up to ~1000kms-1) is also observed in HI in the radio source 4C12.50. As the radio source evolves, any obscuring material along the radio axis is swept aside until, eventually, cavities (of the same kind as observed e.g. in Cygnus A) are hollowed out on either side of the nucleus. We may witness this phase in the evolution of a radio source in the radio galaxy 3C459.
- Publication:
-
Publications of the Astronomical Society of Australia
- Pub Date:
- 2003
- DOI:
- 10.1071/AS02056
- arXiv:
- arXiv:astro-ph/0212321
- Bibcode:
- 2003PASA...20..129M
- Keywords:
-
- galaxies: ISM;
- galaxies: active;
- radio lines: galaxies;
- Astrophysics
- E-Print:
- 8 pages (5 figures of which one in gif format). Will appear in Publications of the Astronomical Society of Australia, as part of the proceedings of the 3rd GPS/CSS workshop, ed. T. Tzioumis, W. de Vries, I. Snellen, A. Koekemoer