Title: The characteristic size of clusters of galaxies - A metric rod used for a determination of the deceleration parameter
Abstract: view Abstract Citations (39) References (25) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS The characteristic size of clusters of galaxies: a metric rod used for a determination of q0. Bruzual, A. G. ; Spinrad, H. Abstract Two definitions of the characteristic size of clusters of galaxies are considered. The harmonic mean separation between the brightest members is found to be very sensitive to the criterion used to select cluster galaxies. The mean distance between the brightest cluster galaxies is used to define a convenient annular spacing, allowing construction of surface density profiles for clusters at every redshift. Cumulative profiles are also considered. Analytical expressions fitted to the profile provide a measurement of a cluster characteristic size. A sample of 54 clusters with redshifts in the range from 0.0207 to 0.9470 are considered. The best solution favors an apparent deceration parameter of 0.25 plus or minus 0.5. Effects of cluster evolution on cluster sizes and on the determination of the deceleration parameter are discussed. No quantitative evalution of this correction is made. Publication: The Astrophysical Journal Pub Date: February 1978 DOI: 10.1086/155875 Bibcode: 1978ApJ...220....1B Keywords: Deceleration; Galactic Clusters; Galactic Evolution; Size Determination; Error Analysis; Red Shift; Spacing; Astrophysics; Clusters of Galaxies:Cosmology full text sources ADS |