2008MNRAS.385...23L -
Mon. Not. R. Astron. Soc., 385, 23-39 (2008/March-3)
Photometric properties and scaling relations of early-type Brightest Cluster Galaxies.
LIU F.S., XIA X.Y., MAO S., WU H. and DENG Z.G.
Abstract (from CDS):
We investigate the photometric properties of the early-type Brightest Cluster Galaxies (BCGs) using a carefully selected sample of 85 BCGs from the C4 cluster catalogue with a redshift of less than 0.1. We perform accurate background subtractions and surface photometry for these BCGs to 25mag/arcsec2 in the Sloan r band. By quantitatively analysing the gradient of the Petrosian profiles of BCGs, we find that a large fraction of BCGs have extended stellar envelopes in their outskirts; more luminous BCGs tend to have more extended stellar haloes that are likely to be connected with mergers. A comparison sample of elliptical galaxies was chosen with similar apparent magnitude and redshift ranges, for which the same photometric analysis procedure is applied. We find that BCGs have steeper size-luminosity (R ∝ Lα) and Faber-Jackson (L ∝ σβ) relations than the bulk of early-type galaxies. Furthermore, the power-law indices (α and β) in these relations increase as the isophotal limits become deeper. For isophotal limits from 22 to 25mag/arcsec2, BCGs are usually larger than the bulk of early-type galaxies, and a large fraction (∼49 per cent) of BCGs have discy isophotal shapes. The differences in the scaling relations are consistent with a scenario where the dynamical structure and formation route of BCGs may be different from the bulk of early-type galaxies; in particular dry (dissipationless) mergers may play a more important role in their formation. We highlight several possible dry merger candidates in our sample.
Abstract Copyright:
2008 The Authors. Journal compilation © 2008 RAS
Journal keyword(s):
galaxies: elliptical and lenticular, cD - galaxies: clusters: general - galaxies: photometry
Simbad objects:
118
Full paper
View the references in ADS
To bookmark this query, right click on this link: simbad:2008MNRAS.385...23L and select 'bookmark this link' or equivalent in the popup menu