Related papers: An X-ray Cluster at Redshift 2.156?
Infrared emission has been detected from normal elliptical galaxies and from clusters of galaxies at 60um and 100um with the IRAS satellite. In both cases, the emission has the characteristics of cool dust with a temperature near 30K. For…
The X-ray properties of a sample of high redshift (z>0.6), massive clusters observed with XMM-Newton and Chandra are described, including two exceptional systems. One, at z=0.89, has an X-ray temperature of T=11.5 (+1.1, -0.9) keV (the…
We report spectropolarimetric observations obtained with the W.M. Keck Telescope of the high redshift z=1.824 aligned radio galaxy 3C256. Our observations confirm that the spatially extended UV continuum emission from this galaxy is…
We present here an efficient method for selecting high luminosity and massive high redshift clusters of galaxies, crucially important tools in cosmology. By selecting bright and extremely X-ray loud (high F(X)/F(V)) sources, we were able to…
At z=0.809, RXJ1716.6+6708 is the second most distant X-ray selected cluster so far published and the only one with a large number of spectroscopically determined cluster member velocities. The optical morphology of RXJ1716.6+6708 resembles…
Recent observations of high energy (> 20 keV) X-ray emission in a few clusters extend and broaden our knowledge of physical phenomena in the intracluster space. This emission is likely to be nonthermal, probably resulting from Compton…
(Abridged) We report the detection of X-ray emission from the host cluster of the radio-quiet quasar H1821+643 with the ROSAT HRI, and the non-detection of the host cluster of the radio-loud quasar 3C206 using the EINSTEIN HRI. CL1821+643…
We present sensitive radio continuum images at high resolution of 37 radio galaxies at z > 2. The observations were made with the Very Large Array (VLA) at 4.7 GHz and 8.2 GHz, with typical resolutions of 0.45'' and 0.25'', respectively.…
To search for a signature of an intracluster magnetic field, we compare measurements of Faraday rotation of polarised extragalactic radio sources in the line of sight of galaxy clusters with those outside. We correlated a catalogue of 1383…
Results are presented of a new VLA-ROSAT study that probes the magnetic field strength and distribution over a sample of 16 ``normal'' low redshift (z < 0.1) galaxy clusters. The clusters span two orders of magnitude in X-ray luminosity,…
The presence of luminous hot X-ray coronae in the dark matter halos of massive spiral galaxies is a basic prediction of galaxy formation models. However, observational evidence for such coronae is very scarce, with the first few examples…
ROSAT High Resolution Imager (HRI) data from eight observations have been co-added to obtain an effective exposure of 230 ksec. We have identified a number of features and regions with excess X-ray brightness over that from a circularly…
Deep ROSAT PSPC and HRI observations of the nuclear starburst, UV flat spectrum spiral NGC6217 reveal a jet-like X-ray filament extending out 2.7' (18.8 kpc) to the SW of the galaxy. Radio images of NGC6217 show an extent in the same…
A2319 is a massive, merging galaxy cluster with a previously detected radio halo that roughly follows the X-ray emitting gas. We present the results from recent observations of A2319 at 20 cm with the Jansky Very Large Array (VLA) and a…
The cluster RX J1347.5-1145, the most luminous cluster in the X-ray wavelengths, was imaged with the newly installed Space Telescope Imaging Spectrograph (STIS) on-board HST. Its relatively high redshift (0.451) and luminosity indicate that…
We report on the XMM-Newton (XMM) observation of RXJ1053.7+5735, one of the most distant X-ray selected clusters of galaxies, which also shows an unusual double-lobed X-ray morphology, indicative of a possible equal-mass cluster merger. The…
We present the results of an extensive spectroscopic survey of RX J0152.7-1357, one of the most massive distant clusters of galaxies known. Multi-object spectroscopy, carried out with FORS1 and FORS2 on the ESO Very Large Telescope (VLT),…
We present spectroscopic confirmation of nine moderate redshift galaxy groups and poor clusters selected from the ROSAT Deep Cluster Survey. The groups span the redshift range z=0.23-0.59 and have between 4 and 20 confirmed members. The…
An analysis of a ROSAT/HRI observation of the optically rich, gravitationally lensing galaxy cluster CL0500-24 (or Abell S0506) is presented. We show that the X-ray luminosity of this supposedly rich cluster is relatively low at…
We present the spectroscopic confirmation of a structure of galaxies surrounding the radio galaxy MRC0156-252 at z = 2.02. The structure was initially discovered as an overdensity of both near-infrared selected z > 1.6 and mid-infrared…