相关论文: RXJ1716.6+6708: a protocluster at z=0.81?
Clusters of galaxies at redshifts nearing one are of special importance since they may be caught at the epoch of formation. At these high redshifts there are very few known clusters. We present follow-up ASCA, ROSAT HRI and Keck LRIS…
We report on the X-ray properties of the exceptional X-ray cluster RXJ1347.5-1145 at z=0.451. We confirm that it is with a luminosity $L_X(bol)=2\times 10^{46}$ erg/s the most luminous X-ray cluster discovered to date. The mass of the…
We present an analysis of the properties of the cluster of galaxies RXJ 1821.6+6827, or NEP 5281, at a redshift z=0.816+/-0.001. RXJ 1821.6+6827 was discovered during the optical identification of the X-ray sources in the North Ecliptic…
We present a multi-wavelength study of RX J0848+4456, a cluster of galaxies discovered through X-ray emission in the ROSAT Deep Cluster Survey. Our observations consist of WFPC2 imaging, optical spectra, and X-ray data collected with the…
We report the discovery of an X-ray luminous galaxy cluster at z =1.11. RDCS J0910+5422 was selected as an X-ray cluster candidate in the ROSAT Deep Cluster Survey on the basis of its spatial extent in a Rosat PSPC image. Deep optical and…
We report on our ASCA, Keck, and ROSAT observations of MS1137.5+6625, the second most distant cluster of galaxies in the Einstein Extended Medium Sensitivity Survey (EMSS), at redshift 0.78. We now have X-ray temperatures, velocity…
In the distant universe X-ray luminous clusters of galaxies are rare objects. Large area surveys are therefore needed to probe the high luminosity end of the cluster population at redshifts z >= 1. We correlated extended X-ray sources from…
We report the discovery of an X-ray luminous galaxy cluster at z=1.26. RXJ0848.9+4452 was selected as an X-ray cluster candidate in the ROSAT Deep Cluster Survey, on the basis of its spatial extent. Deep optical and near-IR imaging have…
An unusual double-lobed extended X-ray source (RX J105343+5735) is detected in the ROSAT ultra-deep HRI image of the Lockman Hole. The angular size of the source is 1.7 X 0.7 arcmin^2 and its X-ray flux is 2 X 10^-14 erg cm^-2 s^-1. R-band…
We observed an extended X-ray source designated as Suzaku J1759-3450 with the Suzaku and Chandra observations towards 1RXS J175911.0-344921, which is an unidentified X-ray source listed in the ROSAT Bright Source Catalogue. A conspicuous…
We present new spectroscopic observations of the most distant X-ray selected galaxy cluster currently known, XMMXCS J2215.9-1738 at z=1.457, obtained with the DEIMOS instrument at the W. M. Keck Observatory, and the FORS2 instrument on the…
We report optical spectroscopic observations of RX J0018.8+1602, a ROSAT X-ray source proposed to be an intermediate redshift cluster of galaxies. Our observations confirm the identification of RX J0018.8+1602 and provide measurements of…
We report the discovery of a massive, X-ray-luminous cluster of galaxies at z=1.393, the most distant X-ray-selected cluster found to date. XMMU J2235.3-2557 was serendipitously detected as an extended X-ray source in an archival XMM-Newton…
The evolution of the properties of the hot gas that fills the potential well of galaxy clusters is poorly known, since models are unable to give robust predictions and observations lack a sufficient redshift leverage and are affected by…
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 report on the discovery of the X-ray luminous cluster XMMU J100750.5+125818 at redshift 1.082 based on 19 spectroscopic members, which displays several strong lensing features. SED modeling of the lensed arc features from multicolor…
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 have selected seven medium-distant clusters of galaxies (z ~ 0.1 - 0.3) for multi-wavelength observations with the goal of investigating their dynamical state. Following Paper I (Pierre et al. 1999) which reported the ASCA results about…
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…
We present imaging and spectroscopic observations of the gravitationally lensed arcs in the field of RX J1347.5-1145, the most X-ray luminous galaxy cluster known. Based on the detection of the [OII] 3727 emission line, we confirm that the…