Open AccessThe cluster of galaxies LCDCS‐S001 – II. r ′ and i ′ photometry, morphological analysis and improved kinematic parameters
Author(s) -
Rembold S. B.,
Pastoriza M. G.
Publication year - 2012
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.1365-2966.2012.20651.x
Subject(s) - physics , astrophysics , velocity dispersion , photometry (optics) , galaxy , cluster (spacecraft) , surface brightness , galaxy cluster , virial theorem , radius , kinematics , bulge , luminosity , astronomy , stars , computer security , classical mechanics , computer science , programming language
We present photometric parameters of the galaxies in the direction of the galaxy cluster LCDCS‐S001 and improved kinematic parameters from new spectroscopic observations. From GMOS multi‐object spectroscopy, we have been able to confirm a new set of 10 cluster members, resulting in a total 22 objects from previous observations. With these data, a dispersion velocity of σ= 887 ± 249 km s −1 , a virial radius R 200 = 0.98 ± 0.22 Mpc and a mass of M 200 = (5.4 ± 2.8) × 10 14 M ⊙ have been derived. From GMOS i ′ and r ′ images, we have extracted the individual sources and derived their magnitudes, relative positions and the bulge+disc brightness profile decomposition. We show that the cluster has an elongated morphology along the north–south direction, with ellipticity ɛ= 0.49 ± 0.14, well represented by a King model with a core radius R C = 283 ± 66 kpc, above the typical core radii of regular clusters. It shows at least one local overdensity, north‐west from the cluster centre, very compact and with a very high central density. The i ′ luminosity function of LCDCS‐S001 has an almost flat faint‐end, α=−1.16 ± 0.18. As for the constituent galaxies, we have found that a large fraction of the cluster galaxies are late‐type systems. Extensive simulations were made in order to verify the validity of our conclusions. We discuss the implication of these results for the evolutionary status of LCDCS‐S001 and conclude that this cluster is still dynamically young.