Diffuse radio emission in the complex merging galaxy cluster Abell2069
Diffuse radio emission in the complex merging galaxy cluster Abell2069
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DOI：
10.1051/0004-6361/201424828
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发表时间：
2014-12
影响因子：
6.5
通讯作者：
A. Drabent;M. Hoeft;R. Pizzo;A. Bonafede;R. Weeren;U. Klein
中科院分区：
文献类型：
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作者：
A. Drabent;M. Hoeft;R. Pizzo;A. Bonafede;R. Weeren;U. Klein
有最近合并迹象的星系团在许多情况下显示出扩展的弥散射电特征。这种发射源自相对论电子，其由于簇内磁场而遭受同步辐射损失。粒子加速的机制和磁场的性质仍然知之甚少。我们在星系团中寻找漫射射电辐射。在这里，我们研究复杂的星系团阿贝尔2069，X射线观测表明最近的合并。我们研究了集群的无线电连续辐射的深韦斯特博克综合射电望远镜（WSRT）在346 MHz的观测和巨米波射电望远镜（GMRT）在322 MHz的观测。我们发现一个扩展的弥漫性无线电功能大致符合集群的主要组成部分。我们将这种发射归类为射电晕，并估计其下限通量密度为25 +/- 9 mJy。此外，我们发现第二个扩展的扩散源位于集群的同伴，估计其通量密度为15 +/- 2 mJy。我们推测这是一个小晕或迷你晕。如果这是真的，这个星系团是第一个在单个星系团中出现双晕的例子。
Galaxy clusters with signs for a recent merger show in many cases extended diffuse radio features. This emission originates from relativistic electrons which suffer synchrotron losses due to the intra-cluster magnetic field. The mechanisms of the particle acceleration and the properties of the magnetic field are still poorly understood. We search for diffuse radio emission in galaxy clusters. Here, we study the complex galaxy cluster Abell 2069, for which X-ray observations indicate a recent merger. We investigate the cluster's radio continuum emission by deep Westerbork Synthesis Radio Telescope (WSRT) observations at 346 MHz and a Giant Metrewave Radio Telescope (GMRT) observation at 322 MHz. We find an extended diffuse radio feature roughly coinciding with the main component of the cluster. We classify this emission as a radio halo and estimate its lower limit flux density to 25 +/- 9 mJy. Moreover, we find a second extended diffuse source located at the cluster's companion and estimate its flux density to 15 +/- 2 mJy. We speculate that this is a small halo or a mini-halo. If true, this cluster is the first example of a double-halo in a single galaxy cluster.