AI 中文总结
本研究利用MeerKAT望远镜观测发现星系团RXC J0528.9−3927存在GHz频率下的射电巨晕候选体，其外部低面亮度辐射构成额外成分，或为首个GHz频射电巨晕。
AI 中文摘要
射电巨晕是近期通过LOFAR观测发现的大规模弥散同步辐射源。我们展示了MeerKAT L波段对大质量星系团RXC J0528.9−3927的观测结果，其中心射电晕周围存在微弱辐射。在1.28 GHz下，已知的约1.14 Mpc晕嵌入此前未报道的延伸至约2 Mpc的低面亮度辐射中。该辐射的面亮度轮廓在约0.55R₅₀₀以外呈现明显变平，表明外部辐射构成额外成分。这些特性使该星系团成为巨晕系统候选，可能是首个在GHz频率下探测到的此类系统，但需更深的多频观测确认。
英文摘要
Radio megahalos are recently discovered large-scale diffuse synchrotron sources identified through LOFAR observations. We present MeerKAT L-band observations of the massive galaxy cluster RXC~J0528.9$-$3927, that reveals faint emission surrounding its central radio halo. At 1.28 GHz, the known $\sim1.14$ Mpc halo is embedded within previously unreported low-surface-brightness emission extending to $\sim2$ Mpc. The surface-brightness profile of the emission shows a distinct flattening beyond $\sim0.55R_{500}$, suggesting that the outer emission forms an additional component. These properties make the cluster a candidate megahalo system and potentially the first detected at GHz frequencies, although deeper multi-frequency observations are required for confirmation.
Comments4 pages, 2 figures, accepted for publication in URSI Radio Science Letters
