1999/10/27 by R. Della Ceca, Della Ceca, R., R. Scaramella +9 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics (astro-ph) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #Stellar, planetary, and galactic studies #astro-ph
paper · pdf · doi:10.48550/arxiv.astro-ph/9910489
10 pages, 7 figures, Latex manuscript, Accepted for publication in the Astronomy and Astrophysics - Main Journal
arxiv created 1999/10/27 · openalex publication_date 1999/10/27 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
We present X-ray observations of two high redshift clusters of galaxies carried out with the BeppoSAX satellite. One cluster, RXJ0152.7-1357 at z = 0.83, was selected from the ROSAT Deep Cluster Survey sample, as one of the most X-ray luminous systems known at z>0.5. The optical and ROSAT-PSPC data show a complex morphology with at least two cores. Our SAX observations yield a gas temperature kT = 6.46+1.74-1.19 keV and a metallicity A = 0.53+0.29-0.24, with a prominent iron K(alpha) line. The second cluster, MS2053.7-0449 at z = 0.58, was selected from the EMSS sample. Given the poor statistics no constraints on the metallicity can be derived from the present data. Large uncertainties are associated to the gas temperature (kT = 6.7+6.8-2.3 keV), which has been obtained after fixing the abundance to 0.3 solar. Combining these results with those obtained for similarly high redshift (z >= 0.5) clusters of galaxies with broad band X-ray spectra, we discuss the high redshift L(bol) - T relationship. The data can easily be accommodated with a non-evolving (or mildly evolving) L(bol) - T relation, a result which, when combined with the little observed evolution in the bulk of the X-ray cluster population, gives support to low Omega cosmological models.