利用X射线成像与光谱任务（XRISM）观测邻近星系团的星系团内介质（ICM）动力学结构

XRISM/Resolve通过直接测量星系团内介质的气体运动，揭示了星系团多样的投影动态。研究通过对比视向速度弥散、整体运动幅度及其比值，分析了冷核与非冷核系统在动力学上的本质差异。这些诊断指标有助于区分局部的中心谱线变宽与更大尺度的相干运动，为理解星系团的演化提供了重要依据。

arXiv:2607.06313v2 Announce Type: replace Abstract: XRISM/Resolve is building a sample of galaxy clusters with directly measured ICM gas motions, revealing diverse projected dynamical states. We compile 45 XRISM/Resolve measurements in 19 nearby galaxy clusters and place them on a common, emission-weighted effective line-of-sight scale, $\ell_{\rm eff}$. We compare the line-of-sight velocity dispersion $\sigma_v$, bulk velocity amplitude $|v_{\rm bulk}|$, their ratio $R_v \equiv |v_{\rm bulk}|/\sigma_v$, and non-thermal pressure proxies. Disturbed non-cool-core systems are not simply higher-dispersion counterparts of relaxed cool-core regions. Instead, differences among cool-core centers, cool-core outer regions, and non-cool-core systems are driven mainly by coherent line-of-sight motion relative to unresolved line broadening: $R_v$ tends to remain below unity in cool-core regions but often exceeds unity in non-cool-core systems, with the mean $R_v$ rising from 0.45 in cool-core centers to 1.6 in non-cool-core systems. These diagnostics help separate local central line broadening, likely associated with AGN feedback in some cool cores, from larger-scale coherent motions associated with sloshing, mergers, and halo assembly. Comparison with forward-modeled TNG-Cluster predictions suggests that many cool-core measurements occupy the lower part of the predicted non-thermal pressure range, consistent with small hydrostatic-mass corrections in relaxed systems and larger corrections in disturbed ones. XRISM is thus beginning