X-ray observations of GPS galaxies: probing the origin of radio powerin the universe
Abstract
We present in this paper the most recent results of XMM-Newton and Chandra observations of Giga-Hertz Peaked Spectrum (GPS) galaxies, a sizable subsample of 5GHz-selected sources in the universe. Their X-ray spectra show substantial column densities when compared to a control sample of "standard" radio galaxies. Together with evidence for large scale radio jets in some GPS quasars, these results challenge the "young" paradigm for the origin of radio power in these cosmological sources, whereby GPS sources represent an infancy stage of large structures. Dense circumnuclear gas may play a fundamental role in braking, or even "choking" the radio jets, while kpc-scale jets may represent the relics of past phases of radio activity, whose "resurrection" at present times we are witnessing.
- Publication:
-
35th COSPAR Scientific Assembly
- Pub Date:
- 2004
- Bibcode:
- 2004cosp...35..517G