Tidally Induced Elongation and Alignments of Galaxy Clusters

Abstract

view Abstract Citations (23) References (44) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Tidally Induced Elongation and Alignments of Galaxy Clusters Salvador-Sole, Eduard ; Solanes, Jose Maria Abstract We show that tidal interaction among galaxy clusters can account for their observed alignments and very marked elongation and, consequently, that these characteristics of clusters are actually consistent with them being formed in hierarchical clustering. The well-established distribution of projected axial ratios of clusters with richness class R ≥ 0 is recovered very satisfactorily by means of a simple model with no free parameters. The main perturbers are relatively rich (R ≥ 1) single clusters and/or groups of clusters (superclusters) of a wider richness class (R ≥ 0) located within a distance of about 65 h-1 Mpc from the perturbed cluster. This makes the proposed scheme be also consistent with all reported alignment effects involving clusters. We find that this tidal interaction is typically in the saturate regime (i.e., the maximum elongation allowed for systems in equilibrium is reached), which explains the very similar intrinsic axial ratio shown by all clusters. Tides would therefore play an important role in the dynamics of large-scale structures; in particular, they should be taken into account when estimating the virial mass of clusters. Publication: The Astrophysical Journal Pub Date: November 1993 DOI: 10.1086/173323 arXiv: arXiv:astro-ph/9304029 Bibcode: 1993ApJ...417..427S Keywords: CELESTIAL MECHANICS; STELLAR DYNAMICS; COSMOLOGY: THEORY; GALAXIES: CLUSTERING; Astrophysics E-Print: 24 pages + 3 figures available upon request, plain TeX, UB-AM-51 full text sources arXiv | ADS |