ABELL 1201: A MINOR MERGER AT SECOND CORE PASSAGE
ABELL 1201: A MINOR MERGER AT SECOND CORE PASSAGE
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ABELL 1201：第二核心通道的小规模合并
DOI：
10.1088/0004-637x/752/2/139
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发表时间：
2012
期刊：
影响因子：
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通讯作者：
W. Couch
中科院分区：
文献类型：
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作者：
Cheng;M. Owers;P. Nulsen;B. McNamara;S. Murray;W. Couch
我们提出了一个合并集群阿贝尔1201的结构和动力学分析，它有两个晃动的冷锋周围的冷却核心，和一个偏移的气体核心约500千秒差距的西北中心。新的钱德拉和XMM-牛顿数据显示，在偏移核心以东有一个亮度增强的区域，其北部和东部的边界沿着有表面亮度的中断。这被解释为从偏移岩心剥离的气体的尾部。偏离核心和尾部的气体与距团中心相同距离的其他气体的区别主要在于具有较高的密度，因此具有较低的熵。此外，偏移核心显示略低于周围地区的温度和金属丰度。冷核的金属丰度较高，而在南方冷锋附近金属丰度突然下降。我们解释所观察到的系统的属性，包括冷锋的位置，偏移的核心，和它的尾巴在一个简单的合并方案。偏移核心是合并子星团的残余，它首先通过主星团中心东南的近心，现在接近第二个近心通道，移动速度为1000 km s−1。合并激发的晃动产生了两个冷锋，冷锋的分布表明我们是从靠近偏置核心轨道平面的位置观察合并的。
We present an analysis of the structures and dynamics of the merging cluster Abell 1201, which has two sloshing cold fronts around a cooling core, and an offset gas core approximately 500 kpc northwest of the center. New Chandra and XMM-Newton data reveal a region of enhanced brightness east of the offset core, with breaks in surface brightness along its boundary to the north and east. This is interpreted as a tail of gas stripped from the offset core. Gas in the offset core and the tail is distinguished from other gas at the same distance from the cluster center chiefly by having higher density, hence lower entropy. In addition, the offset core shows marginally lower temperature and metallicity than the surrounding area. The metallicity in the cool core is high and there is an abrupt drop in metallicity across the southern cold front. We interpret the observed properties of the system, including the placement of the cold fronts, the offset core, and its tail in terms of a simple merger scenario. The offset core is the remnant of a merging subcluster, which first passed pericenter southeast of the center of the primary cluster and is now close to its second pericenter passage, moving at ≃ 1000 km s−1. Sloshing excited by the merger gave rise to the two cold fronts and the disposition of the cold fronts reveals that we view the merger from close to the plane of the orbit of the offset core.