星系团和星系群中弥漫射电源的形成和演化

计划基于Press-Schechter理论对星系团和星系群的并合过程进行流体动力学模拟，辅之以湍流加速和激波加速模型，构建本领域内第一个系统完整的ICM射电展源（主要针对射电晕和射电遗迹）形成和演化模型。为约束该模型，拟利用射电观测数据库和我们已建立的Chandra-XMM星系团X射线大样本，选择含ICM射电展源的星系团构建一个大型射电-X射线样本，系统研究ICM射电展源的物理属性及其各种射电-X射线关联，并对上述模型进行优化。将以优化后的模型解答星系群和贫星系团中ICM射电展源的缺失之谜，阐明极陡谱射电晕和微射电晕的起源。为配合上述工作，将进一步开展星系群和贫星系团的MWA低频射电观测。项目申请人和团队在过去二十多年的工作积累以及近两年的预研究（成果已陆续开始发表）将能有效保障本项目的顺利运行。

We propose to study the formation and evolution of diffuse radio sources in galaxy clusters and groups by carrying out hydrodynamic simulations of cluster/group-scale merger processes, for which both the Press-Schechter formalism and the turbulence/shock re-acceleration models are employed. In order to constrain the simulations we will construct and analyze a large radio-X-ray sample of galaxy clusters and groups that exhibit at least one type of the diffuse radio sources, the data of which will be drawn from the archive Chandra, XMM-Newton, NVSS survey, TGSS survey and MWA GLEAM survey databases, and will use the derived imaging and spectral results, including the radio-X-ray correlations, to optimize our model. We will apply the obtained model to investigate whether or not there exist a large amount faint low frequency diffuse radio sources in galaxy groups and poor clusters, and to explain the origins of ultra-steep spectrum sources and mini-radio halos. We will also apply for new MWA observations to study galaxy groups and poor clusters in the low frequency radio band.