2011/10/31 by Włodzimierz Godłowski, Wlodzimierz Godlowski
Physics and Astronomy · #Brightest cluster galaxy #Cluster (spacecraft) #Elliptical galaxy #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy cluster #Galaxy groups and clusters #Position (finance) #Radio galaxy #Scientific Research and Discoveries #Statistical Mechanics and Entropy #astro-ph.CO #astro-ph.GA
paper · pdf · doi:10.1088/0004-637x/747/1/7
published as 2012 APJ 747, 7 · APJ accepted, Some references are missing in arXive and ADS - see PDF file
arxiv created 2011/12/02 · openalex publication_date 2012/02/08 · arxiv updated 2012/02/14 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
In the 1975 Hawley and Peebles proposed the use of three statistical tests for investigations of galaxy orientations in the large structures. Nowadays, it is considered as the standard method of searching for galactic alignments. In the present paper we analyzed the tests in detail and proposed a few improvements. Based on the improvements, a new method of analysis of the alignment of galaxies in clusters is proposed. The power of this method is demonstrated on the sample of 247 Abell clusters with at least 100 objects in each. The distributions of the position angles for galaxies in each cluster are analyzed using statistical tests: χ 2 , Fourier, autocorrelation, and Kolmogorov test. The mean value of analyzed statistics is compared with theoretical predictions as well as with results obtained from numerical simulations. We performed 1000 simulations of 247 fictitious clusters, each with the numbers of galaxies the same as in the real clusters. We found that orientations of galaxies in analyzed clusters are not random, i.e., that there exists an alignment of galaxies in rich Abell galaxy clusters.