2002/11/13 by Haruyoshi Katayama, Kiyoshi Hayashida, Fumio Takahara +1 · 2 citations
Physics and Astronomy · #Astronomy #Astronomy and Astrophysical Research #Astrophysics #Astrophysics and Star Formation Studies #Brightest cluster galaxy #Cluster (spacecraft) #Fundamental plane (elliptical galaxies) #Galaxies: Formation, Evolution, Phenomena #Galaxy #Galaxy cluster #Physics #Redshift #Surface brightness #Virial theorem #astro-ph
paper · pdf · doi:10.1086/346126
published as Astrophys.J. 585 (2003) 687-693 · 18 pages, 9 figures, accepted for publication in ApJ
arxiv created 2002/11/13 · openalex publication_date 2003/03/10 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
We investigate the relation between the properties of brightest cluster galaxies (BCGs) and those of their host clusters. To quantify the properties of cluster hot gas, we employ the parameter Z of the fundamental plane of X-ray clusters. It is found that the offset of the BCG from the peak of cluster X-ray emission is larger for smaller Z clusters. The parameter Z (not the redshift z ), which depends mainly on virial density ρ vir , is considered to represent the formation epoch of a cluster. We thus consider that the offset of the BCG is correlated with the dynamical equilibrium state of its host cluster. On the contrary, no significant correlation is found between the absolute optical magnitude of the BCG and the parameter Z . If the extreme brightness of the BCG is acquired mainly in the course of cluster evolution by environmental effect, BCGs are expected to be brighter in large Z clusters. Our result is not consistent with this simplified view. On the contrary, it is possible that the extreme brightness of the BCG is likely to be determined in the early history of cluster collapse.