An X-ray Cluster at Redshift 2.156?
Abstract
We present X-ray observations of the narrow line radio galaxy 1138-262 at z = 2.156 with the High Resolution Imager (HRI) on ROSAT. Observations at other wave-bands, and in particular extremely high values of Faraday rotation of the polarized radio emission, suggest that the 1138-262 radio source is in a dense environment, perhaps a hot, cluster-type atmosphere. We detect X-ray emission from the vicinity of 1138-262, and we discuss possible origins for this emission. The X-ray, optical, and radio data all favor thermal emission from a hot cluster atmosphere as the mechanism responsible for the X-rays, although we cannot rule out a contribution from the active nucleus. If this interpretation is correct, then 1138-262 becomes the most distant, by far, of known X-ray emitting clusters. The X-ray luminosity for 1138-262 is 6.7+/-1.3 x 10**44 ergs/sec for emitted energies between 2 keV and 10 keV.
Cite
@article{arxiv.astro-ph/9712253,
title = {An X-ray Cluster at Redshift 2.156?},
author = {C. L. Carilli and D. E. Harris and L. Pentericci and H. J. A. Rottgering and G. K. Miley and M. N. Bremer},
journal= {arXiv preprint arXiv:astro-ph/9712253},
year = {2015}
}