2001/01/30 by Yan-Jie Xue, Yan‐Jie Xue, Xiangping Wu +1
Physics and Astronomy · #Astrophysics #Astrophysics and Cosmic Phenomena #Astrophysics and Star Formation Studies #COSMIC cancer database #Cluster (spacecraft) #Cosmology #Formalism (music) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Luminosity #Luminosity function #Physics #Redshift #astro-ph
paper · pdf · doi:10.1086/320558
6 pages, 2 figures, accepted for publication in ApJ
arxiv created 2001/01/30 · openalex publication_date 2001/05/10 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present a comparison of the Sunyaev-Zeldovich (SZ) cluster counts predicted by the Press-Schechter (PS) mass function (MF) and the X-ray luminosity function (XLF) of clusters. The employment of the cluster XLF, together with the observationally determined X-ray luminosity-temperature ( L X - T ) relation, may allow us to estimate the SZ cluster counts in a more realistic manner, although such an empirical approach depends sensitively on our current knowledge of the dynamical properties of intracluster gas and its cosmic evolution. Using both the nonevolving and evolving XLFs of clusters suggested by X-ray observations, we calculate the expectations for SZ surveys of clusters with X-ray luminosity L X ≥ 3 × 10 44 ergs s -1 and L X ≥ 1 × 10 43 ergs s -1 in the 0.5-2.0 band, respectively. The nonevolving XLF results in a significant excess of SZ cluster counts at high redshifts as compared with the evolving XLF, while a slightly steeper L X - T relation than the observed one is needed to reproduce the distributions of SZ clusters predicted by the standard PS formalism. It is pointed out that uncertainties in the cosmological application of future SZ cluster surveys via the standard PS formalism should be carefully studied.