On the Study of the Substructure of Galaxy Clusters: S-Tree Technique in Non-Point Approximation

K. M. Bekarian; A. A. Melkonian

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On the Study of the Substructure of Galaxy Clusters: S-Tree Technique in Non-Point Approximation

K. M. Bekarian·A. A. Melkonian

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Abstract

We represent the further development of S-tree technique of the study the structure of clusters of galaxies. The S-tree technique developed by Gurzadyan et al enables one to analyse the substructures of clusters via self-consistent use of 2D positional, 1D kinematical and magnitude information on the galaxies. First, the generalization of the method for the system of N-spheres, i.e. in non-point approximation, is performed, and the ways of construction of a new $D$ matrix are given. Second, an efficient algorithm for analyzing of the S-tree output information is presented, enabling one to reveal the existence of subgroups and the membership of galaxies in each subgroup.

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K. M. Bekarian, A. A. Melkonian. 1997-04-07. On the Study of the Substructure of Galaxy Clusters: S-Tree Technique in Non-Point Approximation. https://arxiv.org/abs/astro-ph/9704054

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