S-tree Analysis of the Substructure of the Coma Cluster

V. G. Gurzadyan; A. Mazure

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arXiv · astro-ph/9710094

S-tree Analysis of the Substructure of the Coma Cluster

V. G. Gurzadyan·A. Mazure

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Abstract

The S-tree method is used to estimate the redshift of the core of Coma cluster - $cz = 6953$ km s$^{-1}$ and dispersion $σ=949$ km s$^{-1}$. The existence of three subgroups of galaxies is revealed, one of them is associated with the cD galaxy NGC 4874, another - with NGC 4889. It is argued that these subgroups are 'galaxy associations', i.e. galactic dynamical entities moving through the main cluster. The non-stationarity of the dynamical processes ongoing in the Coma core is concluded.

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V. G. Gurzadyan, A. Mazure. 1997-10-09. S-tree Analysis of the Substructure of the Coma Cluster. https://arxiv.org/abs/astro-ph/9710094

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