Galaxy and hot gas distributions in the z = 0.52 galaxy cluster RBS 380 from CHANDRA and NTT observations
Institute für Physik, Universität Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany
2 Institut für Astrophysik, Universität Innsbruck, Technikerstr. 25, 6020 Innsbruck, Austria e-mail: Sabine.Schindler@uibk.ac.at
Corresponding author: R. Gil-Merino, firstname.lastname@example.org
Accepted: 17 June 2003
We present CHANDRA X-ray and NTT optical observations of the distant galaxy cluster RBS 380 – the most distant cluster of the ROSAT Bright Source (RBS) catalogue. We find diffuse, non-spherically symmetric X-ray emission with a X-ray luminosity of erg/s, which is lower than expected from the RBS. The reason is a bright AGN in the centre of the cluster contributing considerably to the X-ray flux. This AGN could not be resolved with ROSAT. In optical wavelength we identify several galaxies belonging to the cluster. The galaxy density is at least 2 times higher than expected for such a X-ray faint cluster, which is another confirmation of the weak correlation between X-ray luminosity and optical richness. The example of the source confusion in this cluster shows how important high-resolution X-ray imaging is for cosmological research.
Key words: galaxies: clusters: general / intergalactic medium / cosmology: observations / cosmology: theory / dark matter / X-rays: galaxies
© ESO, 2003