我们测量了ACS天炉座星系团巡天（ACSFCS）中43个星系的球状星团（GC）的半光半径。我们使用这些数据来扩展以前的工作，其中的环境依赖性的早期类型星系的GC在ACS室女星系团调查（ACSVCS）进行了研究，并建议作为一个可靠的距离指标的校正的平均半光半径（校正所观察到的环境趋势）。这项工作既增加了研究环境依赖性的样本量，又增加了研究校正后的半光半径作为可能的距离指标的杠杆作用（因为天炉座比室女星系团距离更远）。我们研究了环境的依赖性的GC的大小，使用主成分分析以及二维尺度关系。我们在很大程度上证实了Jordan et al.（2005）中所显示的环境依赖性，但发现有证据表明GC系统的平均半光半径与星系星等之间存在残余相关性，而其他相关性则存在细微差异-因此对于较低光度星系GC系统的半光半径可能不存在普适校正。决定早期星系GC大小的主要因素是GC颜色。红色GC具有<r_h>= 2.8+/-0.3 pc，而蓝色GC具有<r_h>= 3.4+/-0.3 pc。结果表明，对于明亮的早型星系（M_B < -19等），GC系统的未校正平均半光半径本身就是一个很好的距离指示器（误差约为11%），在大型光学望远镜的高角分辨率自适应光学时代，它有可能达到宇宙学上感兴趣的距离。
英文摘要：
We measure the half-light radii of globular clusters (GCs) in 43 galaxies from the ACS Fornax Cluster Survey (ACSFCS). We use these data to extend previous work in which the environmental dependencies of the half-light radii of GCs in early type galaxies in the ACS Virgo Cluster Survey (ACSVCS) were studied, and a corrected mean half-light radius (corrected for the observed environmental trends) was suggested as a reliable distance indicator. This work both increases the sample size for the study of the environmental dependencies, and adds leverage to the study of the corrected half-light radius as a possible distance indicator (since Fornax lies at a larger distance than the Virgo cluster). We study the environmental dependencies of the size of GCs using both a Principal Component Analysis as well as 2D scaling relations. We largely confirm the environmental dependencies shown in Jordan et al. (2005), but find evidence that there is a residual correlation in the mean half-light radius of GC systems with galaxy magnitude, and subtle differences in the other correlations - so there may not be a universal correction for the half-light radii of lower luminosity galaxy GC systems. The main factor determining the size of a GC in an early type galaxy is the GC color. Red GCs have <r_h> = 2.8+/-0.3 pc, while blue GCs have <r_h> = 3.4+/-0.3 pc. We show that for bright early-type galaxies (M_B < -19 mag), the uncorrected mean half-light radius of the GC system is by itself an excellent distance indicator (with error ~11%), having the potential to reach cosmologically interesting distances in the era of high angular resolution adaptive optics on large optical telescopes.
The ACS Fornax Cluster Survey. IV. Deprojection of the Surface Brightness Profiles of Early-Type Galaxies in the Virgo and Fornax Clusters: Investigating the "Core/Power-Law Dichotomy"
The ACS Fornax Cluster Survey. V. Measurement and Recalibration of Surface Brightness Fluctuations and a Precise Value of the Fornax--Virgo Relative Distance
The MeerKAT Fornax Survey VII. Characterisation of the Fornax cluster's magnetic field and new insights on magnetisation in large scale systems
INAF - Osservatorio Astronomico di Cagliari（意大利国家天体物理研究所卡利亚里天文台）；Wits Centre for Astrophysics, School of Physics, University of the Witwatersrand（威特沃特斯兰德大学物理学院天体物理中心）；Ruhr University Bochum（鲁尔大学波鸿分校）；Netherlands Institute for Radio Astronomy (ASTRON)（荷兰射电天文研究所）
The ACS Fornax Cluster Survey. VIII. The Luminosity Function of Globular Clusters in Virgo and Fornax Early-Type Galaxies and its Use as a Distance Indicator
