2010/09/06 by Włodzimierz Godłowski, Wlodzimierz Godlowski, Paulina Piwowarska +2
Physics and Astronomy · #Brightest cluster galaxy #Cluster (spacecraft) #Elliptical galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy cluster #Galaxy groups and clusters #Interacting galaxy #Lenticular galaxy #Orientation (vector space) #Scientific Research and Discoveries #Statistical Mechanics and Entropy #Velocity dispersion #astro-ph.CO
paper · pdf · doi:10.1088/0004-637x/723/2/985
published as Astrophysical Journal 723 (2010) 985-992 · APJ accepted, 41 pages, 5 figures, 4 tables
arxiv created 2010/09/06 · openalex publication_date 2010/10/18 · arxiv updated 2015/05/19 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
We present an analysis of the spatial orientations of galaxies in 247 optically selected rich Abell clusters which have at least 100 members in the considered area. We investigated the relation between angles that give information about galaxy angular momenta and the number of members in each structure. The position angles of the galaxies' major axes, as well as two angles describing the spatial orientation of the galaxy plane, were tested for isotropy by applying three different statistical tests. It is found that the values of the statistics increase with the amount of the galaxies' members, which is equivalent to the existence of a relation between anisotropy and the number of galaxies in a cluster. The search for connection between the galaxies' alignments and Bautz–Morgan (BM) morphological types of examined clusters showed a weak dependence. A statistically marginal relation between velocity dispersion and cluster richness was observed. In addition, it was found that the velocity dispersion decreases with BM type at almost 3σ level. These results show the dependence of alignments with respect to clusters' richness, which can be regarded as an environmental effect.