1997/10/27 by P. Rosati, R. Della Ceca, Colin Norman +2 · 13 citations
Chemistry · Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysical Phenomena and Observations #Astrophysics #Chemistry #Cluster (spacecraft) #Flux (metallurgy) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Luminosity #Luminosity function #Physics #ROSAT #Redshift #Sky #astro-ph
paper · pdf · doi:10.1086/311085
published as Astrophys.J. 492 (1998) L21 · 12 pages, 4 figures, LaTeX (aasms4.sty). To appear in ApJ Letters
arxiv created 1997/10/27 · openalex publication_date 1998/01/01 · arxiv updated 2009/12/01 · openalex created_date 2019/06/27 · openalex updated_date 2026/08/05
We present the X-ray luminosity function (XLF) of the ROSAT Deep Cluster Survey sample over the redshift range 0.05-0.8. Our results are derived from a complete flux-limited subsample of 70 galaxy clusters, representing the brightest half of the total sample, which have been spectroscopically identified down to the flux limit of 4 × 10 −14 ergs m -2 s -1 (0.5-2.0 keV) and have been selected via a serendipitous search in ROSAT PSPC pointed observations. The redshift baseline is large enough that evolutionary effects can be studied within the sample. The local XLF ( z ≤0.25) is found to be in excellent agreement with previous determinations using ROSAT All-Sky Survey data. The XLF at higher redshifts, when combined with the deepest number counts constructed to date ( f >2 × 10 −14 ergs cm −2 s −1 ), reveals no significant evolution at least out to z =0.8, over a luminosity range of 2 × 10 42 to 3 × 10 44 ergs s −1 in the 0.5-2 keV band. These findings extend the study of cluster evolution to the highest redshifts and the faintest fluxes probed so far in X-ray surveys. They complement and do not necessarily conflict with those of the Einstein Extended Medium-Sensitivity Survey, leaving open the possibility of negative evolution of the brightest end of the XLF at high redshifts.