Open AccessSubstructure analysis of selected low‐richness 2dFGRS clusters of galaxies
Author(s) -
Burgett William S.,
Vick Michael M.,
Davis David S.,
Colless Matthew,
De Propris Roberto,
Baldry Ivan,
Baugh Carlton,
BlandHawthorn Joss,
Bridges Terry,
Can Russell,
Cole Shaun,
Collins Chris,
Couch Warrick,
Cross Nicholas,
Dalton Gavin,
Driver Simon,
Efstathiou George,
Ellis Richard,
Frenk Carlos S.,
Glazebrook Karl,
Hawkins Edward,
Jackson Carole,
Lahav Ofer,
Lewis Ian,
Lumsden Stuart,
Maddox Steve,
Madgwick Darren,
Norberg Peder,
Peacock John A.,
Percival Will,
Peterson Bruce,
Sutherland Will,
Taylor Keith
Publication year - 2004
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1111/j.1365-2966.2004.07952.x
Subject(s) - substructure , physics , supercluster (genetic) , astrophysics , cluster (spacecraft) , galaxy cluster , galaxy , redshift , galaxy groups and clusters , astronomy , biochemistry , chemistry , phylogenetics , structural engineering , computer science , engineering , gene , programming language
Complementary one‐, two‐ and three‐dimensional tests for detecting the presence of substructure in clusters of galaxies are applied to recently obtained data from the 2dF Galaxy Redshift Survey. The sample of 25 clusters used in this study includes 16 clusters not previously investigated for substructure. Substructure is detected at or greater than the 99 per cent confidence level in at least one test for 21 of the 25 clusters studied here. From the results, it appears that low‐richness clusters commonly contain subclusters participating in mergers. About half of the clusters have two or more components within 0.5 h −1 Mpc of the cluster centroid, and at least three clusters (Abell 1139, Abell 1663 and Abell S333) exhibit velocity–position characteristics consistent with the presence of possible cluster rotation, shear, or infall dynamics. The geometry of certain features is consistent with influence by the host supercluster environments. In general, our results support the hypothesis that low‐richness clusters relax to structureless equilibrium states on very long dynamical time‐scales (if at all).