期刊
ASTROPHYSICAL JOURNAL
卷 713, 期 2, 页码 1037-1047出版社
IOP PUBLISHING LTD
DOI: 10.1088/0004-637X/713/2/1037
关键词
galaxies: clusters: general; galaxies: clusters: intracluster medium; galaxies: elliptical and lenticular, cD; X-rays: galaxies: clusters
资金
- National Aeronautics and Space Administration
- National Science Foundation
- Alfred P. Sloan Foundation
- U.S. Department of Energy
- Japanese Monbukagakusho
- Max Planck Society
- Higher Education Funding Council for England
- STFC [ST/G003084/1] Funding Source: UKRI
- Science and Technology Facilities Council [ST/G003084/1] Funding Source: researchfish
We investigate the relationship between brightest cluster galaxies (BCGs) and their host clusters using a sample of nearby galaxy clusters from the Representative XMM-Newton Cluster Structure Survey. The sample was imaged with the Southern Observatory for Astrophysical Research in R band to investigate the mass of the old stellar population. Using a metric radius of 12 h(-1) kpc, we found that the BCG luminosity depends weakly on overall cluster mass as L(BCG) proportional to M(cl)(0.18 +/- 0.07), consistent with previous work. We found that 90% of the BCGs are located within 0.035 r500 of the peak of the X-ray emission, including all of the cool core (CC) clusters. We also found an unexpected correlation between the BCG metric luminosity and the core gas density for non-cool-core (non-CC) clusters, following a power law of n(e) proportional to L(BCG)(2.7 +/- 0.4) (where ne is measured at 0.008 r(500)). The correlation is not easily explained by star formation (which is weak in non-CC clusters) or overall cluster mass (which is not correlated with core gas density). The trend persists even when the BCG is not located near the peak of the X-ray emission, so proximity is not necessary. We suggest that, for non-CC clusters, this correlation implies that the same process that sets the central entropy of the cluster gas also determines the central stellar density of the BCG, and that this underlying physical process is likely to be mergers.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据