The baryonic haloes of elliptical galaxies: radial distribution of globular clusters and diffuse hot gas
The baryonic haloes of elliptical galaxies: radial distribution of globular clusters and diffuse hot gas
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椭圆星系的重子晕：球状星团的径向分布和弥漫的热气体
DOI：
10.1111/j.1365-2966.2012.21368.x
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发表时间：
2012
影响因子：
4.8
通讯作者：
E. O’Sullivan
中科院分区：
文献类型：
--
作者：
D. Forbes;T. Ponman;E. O’Sullivan
对于一个样本的9个研究的巨大的椭圆，我们比较了投影径向分布的红色和蓝色球状星团（GC）的子人口与他们的宿主星系恒星和X射线表面亮度配置文件。我们支持以前的研究结果，红色（富含金属）GC的表面密度分布如下的宿主星系星光。我们发现蓝色GC表面密度的外斜率和星系X射线发射之间有很好的一致性。投影径向轮廓的这种重合可能是由于蓝色GC和X射线发射热气体在平衡时共享相同的引力势。当去投影时，X射线发射热气体具有径向密度依赖性，其是GC密度的平方根。我们进一步表明，每单位质量的蓝色GC的能量大约是一半的热气体。
For a sample of nine well-studied giant ellipticals, we compare the projected radial distribution of their red and blue globular cluster (GC) subpopulations with their host galaxy stellar and X-ray surface brightness profiles. We support previous findings that the surface density distribution of red (metal-rich) GCs follows that of the host galaxy starlight. We find good agreement between the outer slope of the blue GC surface density and that of the galaxy X-ray emission. This coincidence of projected radial profiles is likely due to the fact that both blue GCs and X-ray emitting hot gas share the same gravitational potential in equilibrium. When deprojected the X-ray emitting hot gas has a radial density dependence that is the square root of that for the GC density. We further show that the energy per unit mass for blue GCs is roughly half that of the hot gas.