EVIDENCE FOR PARTICLE RE-ACCELERATION IN THE RADIO RELIC IN THE GALAXY CLUSTER PLCKG287.0+32.9
EVIDENCE FOR PARTICLE RE-ACCELERATION IN THE RADIO RELIC IN THE GALAXY CLUSTER PLCKG287.0+32.9
复制标题
DOI：
10.1088/0004-637x/785/1/1
复制
发表时间：
2014-04-10
影响因子：
4.9
通讯作者：
Roettgering, H. J. A.
中科院分区：
文献类型：
--
作者：
Bonafede, A.;Intema, H. T.;Roettgering, H. J. A.
射电遗迹是在星系团中观测到的弥散射电源，可能是由星系团合并过程中的冲击加速产生的。它们的大尺寸，约为1 Mpc，表明发射电子需要局部加速。通常引用的扩散冲击加速模型已受到最近的观察和理论的挑战。本文报道了在银河系星团PLCKG 287.0 +32.9中发现的复杂射电辐射，该星系团有两个遗迹，一个射电晕和几个射电遗迹辐射。光学观测表明，该星团是拉长的，很可能是沿着一条星系际暗条，并显示出大量的亚结构。这个射电遗迹的特殊特征是：（1）它似乎与射电星系的叶相连;（2）射电遗迹两侧的射电频谱变陡。我们讨论的背景下，粒子再加速这些功能的起源。
Radio relics are diffuse radio sources observed in galaxy clusters, probably produced by shock acceleration during cluster-cluster mergers. Their large size, of the order of 1 Mpc, indicates that the emitting electrons need to be (re) accelerated locally. The usually invoked diffusive shock acceleration models have been challenged by recent observations and theory. We report the discovery of complex radio emission in the Galaxy cluster PLCKG287.0+32.9, which hosts two relics, a radio halo, and several radio filamentary emission. Optical observations suggest that the cluster is elongated, likely along an intergalactic filament, and displays a significant amount of substructure. The peculiar features of this radio relic are that (1) it appears to be connected to the lobes of a radio galaxy and (2) the radio spectrum steepens on either side of the radio relic. We discuss the origins of these features in the context of particle re-acceleration.