论文标题
在加拿大法国夏威夷望远镜传统调查中检测到的一千多个最亮星系的物理特性
Physical properties of more than one thousand brightest cluster galaxies detected in the Canada France Hawaii Telescope Legacy Survey
论文作者
论文摘要
最明亮的簇星系（BCG）是在集群中心发现的非常巨大的椭圆星系。他们的研究提供了有关嵌入簇的形成和演变的线索。我们在这里以均匀的方式分析了红移范围内超过一千个BCG的样品的性质，该样本基于加拿大法国夏威夷望远镜传统调查的图像。基于Sarron等人的1371群集群目录。 （2018年），我们应用了自动BCG检测算法，并在样本中成功识别了70％的BCG。我们用Galfit分析了他们的2D光度特性。我们还将BCG主要轴的位置角与它们所属的整体簇的位置角度进行了比较。我们发现，与Chu等人的先前结果一致，红移最高为Z = 0.7的BCG性质没有演变。 （2021），他分析了一个较小的样本级，但达到红移Z = 1.8。 BCG的Kormendy关系紧密，并且与其他作者测量的正常椭圆星系和BCG的关系一致。 BCG的位置角度和它们所属的群集的位置角度在30度以内同意，其中55％的位置角度角度的对象。对一千多个BCG的非常大样本的研究表明，它们主要是在z = 0.7之前形成的，因为我们发现中央星系的亮度和尺寸没有显着的生长。我们讨论了群内光在解释这些结果中的重要性。我们强调了图像深度在BCG的亮度曲线模型中的作用，并为存在内部结构的存在提供了证据，该结构只能在深度调查中解析，并以80％完整性m80> 26 mag/arcsec2在深度范围内清晰地调查。
Brightest cluster galaxies (BCGs) are very massive elliptical galaxies found at the centers of clusters. Their study gives clues on the formation and evolution of the clusters in which they are embedded. We analysed here in a homogeneous way the properties of a sample of more than one thousand BCGs in the redshift range 0.15 < z < 0.7, based on images from the Canada France Hawaii Telescope Legacy Survey. Based on the cluster catalogue of 1371 clusters by Sarron et al. (2018), we applied our automatic BCG detection algorithm and identified successfully 70% of the BCGs in our sample. We analysed their 2D photometric properties with GALFIT. We also compared the position angles of the BCG major axes with those of the overall cluster to which they belong. We found no evolution of the BCG properties with redshift up to z = 0.7, in agreement with previous results by Chu et al. (2021), who analysed an order of magnitude smaller sample, but reaching a redshift z = 1.8. The Kormendy relation for BCGs is tight and consistent with that of normal elliptical galaxies and BCGs measured by other authors. The position angles of the BCGs and of the cluster to which they belong agree within 30 degrees for 55% of the objects with well defined position angles. The study of this very large sample of more than one thousand BCGs shows that they were mainly formed before z = 0.7, as we find no significant growth for the luminosities and sizes of central galaxies. We discuss the importance of the intracluster light in the interpretation of these results. We highlight the role of image depth in the modelisation of the luminosity profiles of BCGs, and give evidence for the presence of an inner structure which can only be resolved on deep surveys with limiting apparent magnitude at 80% completeness m80 > 26 mag/arcsec2.
