Clustering and properties of K-band companion galaxies around ultrasteep spectrum radio sources
Clustering and properties of K-band companion galaxies around ultrasteep spectrum radio sources
复制标题
超陡频谱射电源周围 K 波段伴星系的聚类和特性
DOI：
10.1111/j.1365-2966.2005.09876.x
复制
发表时间：
2005
影响因子：
4.8
通讯作者：
H Germany
中科院分区：
文献类型：
--
作者：
C. Bornancini;D. Lambas;Carlos De Breuck Iate;Observatorio Astronomico de Cordoba;Argentina.;E. Observatory;Garching;H Germany
我们已经分析了星系的性质，在环境中的一个样本的70超陡谱（USS）的无线电源从悉尼大学莫龙洛巡天和国家射电天文台（NRAO）甚大阵巡天目录，使用近红外数据完成到KS = 20。我们已经量化了星系过剩的USS目标周围使用阿贝尔型测量N 0.5。我们发现，大多数USS领域的研究是兼容的阿贝尔类0丰富的集群。对USS射电源周围伴星系分布的统计分析表明，在射电轴定义的方向上发现这样的物体的趋势很明显，这表明它们可能与射电源的存在有关。我们还测量了中心浓度的光的USS样品，并将这些值进行了比较，使用其他方法选择的场星系和星系。通过使用斯皮尔曼统计解开丰富和浓度指数的依赖性，我们发现一个弱，但显着的，正相关。我们发现，在z > 2 USS射电源更集中比场星系在类似的红移，这表明这些对象跟踪最大规模的系统在高红移。
We have analysed galaxy properties in the environment of a sample of 70 ultrasteep spectrum (USS) radio sources selected from the Sydney University Molonglo Sky Survey and the National Radio Astronomy Observatories (NRAO) Very Large Array Sky Survey catalogues, using near-infrared data complete down to K s = 20. We have quantified galaxy excess around USS targets using an Abell-type measurement N 0.5 . We find that most of the USS fields studied are compatible with being Abell class 0 richness clusters. A statistical analysis of the distribution of companion galaxies around USS radio sources shows a pronounced tendency for such objects to be found in the direction defined by the radio axis, suggesting that they may be related to the presence of the radio sources. We have also measured the central concentration of light of the USS sample and compared these to the values obtained for field galaxies and galaxies selected using other methods. By using Spearman statistics to disentangle richnesses and concentration indices dependences, we detect a weak, but significant, positive correlation. We find that at z > 2 USS radio sources are more concentrated than field galaxies at similar redshifts, indicating that these objects trace the most massive systems at high redshift.