论文标题
簇内光及其与宿主群集特性的相关性的光度清理
Photometric dissection of Intracluster Light and its correlations with host cluster properties
论文作者
论文摘要
我们使用表面亮度切割，亮度切割，透明度切割，多余的光线或双重分解，探索了几种探索最亮星系星系（BCG）及其周围簇内光（ICL）的方法。假设所有光线以上的所有光<-21.85〜g'〜 \ rm {mag} $均可归因于ICL，我们发现平均ICL分数为$ f^{\ rm mt} _ {\ rm icl iCl} = 71 \ pm22 \ pm22 \ pm22 \％diffuse Light centercement the ICL属于iCl bc bc bc bc bc bc bc bc bc c。同样，如果我们假设所有轻度的轻度比$ \ rm {sb}> 27 $ $ $ g'u $ mag arcsec $^{ - 2} $属于ICL，则平均ICL分数为$ f^{\ rm sb27} _ {\ rm icl icl iCl} = 34 \ pm19 \％$ $ $ $ $。在将de vaucouleurs拟合到SB轮廓的内部部分之后，我们在大半径上检测到多余的光，对应于$ f^{\ rm dv} _ {\ rm icl iCl} = 48 \ pm20 \％$的平均ICL分数。最后，通过将SB配置文件分解为两个sérsic函数，我们发现平均ICL分数为$ f^{\ rm s \ times} _ {\ rm iCl} = 52 \ pm21 \％$ $与外部sérsic成分相关。我们测得的ICL和BCG+ICL光度与高分辨率模拟的预测非常吻合，其中外部Sérsic成分追踪了未放松的，积聚的恒星材料。以这种方式定义的BCG和ICL属性与群集参数相关，以研究BCG，ICL及其宿主簇的共同进化。我们发现BCG+ICL亮度与簇质量，簇速度分散，簇半径和集成的卫星亮度之间的正相关性，证实BCG/ICL的生长确实与簇增长相结合。平均而言，就位置角，椭圆度和居中而言，ICL比BCG与宿主群集更好。这使其成为潜在的暗物质示踪剂。
We explore several ways to dissect Brightest Cluster Galaxies (BCGs) and their surrounding Intracluster Light (ICL) using a surface brightness cut, a luminosity cut, excess light above a de Vaucouleurs profile, or a double Sérsic decomposition. Assuming that all light above $M<-21.85~g'~\rm{mag}$ is attributable to the ICL, we find an average ICL fraction of $f^{\rm MT}_{\rm ICL}=71\pm22\%$ of all diffuse light centered on the BCG to belong to the ICL. Likewise, if we assume all light fainter than $\rm{SB}>27$ $g'$ mag arcsec$^{-2}$ to belong to the ICL, the average ICL fraction is $f^{\rm SB27}_{\rm ICL}=34\pm19\%$. After fitting a de Vaucouleurs profile to the inner parts of the SB profile, we detect excess light at large radii, corresponding to an average ICL fraction of $f^{\rm DV}_{\rm ICL}=48\pm20\%$. Finally, by decomposing the SB profile into two Sérsic functions, we find an average ICL fraction of $f^{\rm S\times}_{\rm ICL}=52\pm21\%$ associated with the outer Sérsic component. Our measured ICL and BCG+ICL luminosities agree well with predictions from high-resolution simulations where the outer Sérsic component traces the unrelaxed, accreted stellar material. BCG and ICL properties defined in this way are correlated with cluster parameters to study the co-evolution of BCGs, ICL, and their host clusters. We find positive correlations between BCG+ICL brightness and cluster mass, cluster velocity dispersion, cluster radius, and integrated satellite brightness, confirming that BCG/ICL growth is indeed coupled with cluster growth. On average, the ICL is better aligned than the BCG with the host cluster in terms of position angle, ellipticity, and centering. That makes it a potential Dark Matter tracer.
