view Abstract Citations (21) References (71) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A ROSAT Search for Clusters Around Three Powerful Radio Galaxies at Redshifts 0.1~<z~<0.25 O'Dea, Christopher P. ; Worrall, D. M. ; Baum, Stefi A. ; Stanghellini, Carlo Abstract We report ROSAT PSPC observations of three powerful radio galaxies. We detect extended emission from the classical double radio galaxy 2053-201 (z = 0.1546) with a 0.2-2 keV luminosity (H_0_ = 75 km s^-1^ kpc^-1^) of L_x_ ~3 x 10^43^ ergs s^-1^, which overlaps the range of luminosities measured for Abell clusters at similar redshifts. We do not detect x-ray emission from the 2 GHz peaked spectrum (GPS) radio galaxies 1345+125 (z = 0.122) and 2352+495 (z = 0.237). The 3σ upper limits to the x-ray luminosity are about L_x_ < 3 x 10^42^ ergs s^-1^, roughly an order of magnitude below the detection of 2053-201. These observations are consistent with the environments of GPS radio galaxies being poor clusters or groups, as indicated by optical imaging. The absence of strong nuclear x-ray emission from the AGN in the GPS galaxies suggests the GPS nuclei are either highly obscured or not intrinsically very powerful x-ray sources. Our x-ray upper limits for the GPS sources rule out two very promising candidates for confining the radio emission to its small subkpc physical size: a hot component of the ISM and a massive cooling flow. Any confining gas must be colder than ~10^6^ K. However, such gas has so far proved somewhat elusive, with existing radio data implying only modest column densities, insufficient to hide significant nuclear x-ray emission. Our x-ray limits allow hot-gas environments and emission components which are more consistent with measured lower-power (FRI) radio galaxies than with higher-power (FR2) sources. Thus, if GPS sources are young versions of powerful extended radio sources, then our results are consistent with them evolving into FRI (or weaker) radio sources, i.e., their radio luminosity declines as the sources age. Publication: The Astronomical Journal Pub Date: January 1996 DOI: 10.1086/117763 Bibcode: 1996AJ....111...92O Keywords: RADIO LINES: GALAXIES; GALAXIES: CLUSTERING full text sources ADS | data products SIMBAD (3) NED (3) HEASARC (1)