Open AccessThe large peculiar velocity of the cD galaxy in Abell 3653
Author(s) -
Pimbblet Kevin A.,
Roseboom Isaac G.,
Doyle Marianne T.
Publication year - 2006
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.1365-2966.2006.10131.x
Subject(s) - physics , astrophysics , velocity dispersion , spectrograph , substructure , galaxy cluster , galaxy , cluster (spacecraft) , abell 2744 , peculiar velocity , brightest cluster galaxy , radial velocity , rest frame , astronomy , redshift , spectral line , stars , structural engineering , computer science , engineering , programming language
We present a catalogue of galaxies in Abell 3653 from observations made with the 2‐degree field (2dF) spectrograph at the Anglo‐Australian Telescope. Of the 391 objects observed, we find 111 are bona fide members of Abell 3653. We show that the cluster has a velocity of cz = 32 214 ± 83 km s −1 ( z = 0.10 738 ± 0.00 027) , with a velocity dispersion typical of rich, massive clusters of σ cz = 880 +66 −54 . We find that the cD galaxy has a peculiar velocity of 683 ± 96 km s −1 in the cluster rest frame – some 7σ away from the mean cluster velocity, making it one of the largest and most significant peculiar velocities found for a cD galaxy to date. We investigate the cluster for signs of substructure, but do not find any significant groupings on any length scale. We consider the implications of our findings on cD formation theories.