AI 中文总结
研究阿贝尔2034星系团的弥漫发射，通过MeerKAT多频率及相关存档观测，结合偏振特性、光谱指数等信息，揭示其复杂形态及磁场特性，确认射电晕等，表明深度多频和偏振观测对理解起源至关重要。
AI 中文摘要
我们展示了对星系团阿贝尔2034的MeerKAT观测结果，它是一个质量巨大（M_500 = 5.21×10^14太阳质量）且处于合并状态的邻近星系团。先前144MHz的观测显示该星系团有大量弥漫发射，因缺乏光谱和偏振观测，多个弥漫源分类不明。此次以816MHz和1.28GHz为中心的MeerKAT多频率观测，结合144MHz的低频LOFAR存档观测，得以揭示这些源的性质。偏振特性和光谱指数信息表明该星系团有一个射电遗迹、一个光谱极陡的源（先前被归类为候选遗迹）以及低频下在尾状射电星系周围的极陡发射细丝。确认了射电晕的存在，其光谱在144MHz至1.28GHz之间显示出曲率迹象。利用L波段的偏振数据和从X射线观测得出的气体密度模型来约束星系团内介质中的磁场。我们假设一个径向对称磁场模型，其强度随星系团气体密度下降，如B(r) ~ n_e(r)^0.5，并在R_500内对其强度进行归一化。我们发现B_500 = 1μG最能解释该星系团的法拉第深度特性，不过探测靠近星系团中心的源对于区分不同值至关重要。我们得出结论，阿贝尔2034星系团显示出形态复杂的弥漫发射，不符合晕和遗迹的传统分类。深度多频率和偏振观测对于理解其起源至关重要。
英文摘要
We present MeerKAT observations of the galaxy cluster Abell 2034, a massive (M_500=5.21 10^14 solar masses) nearby cluster in a merging state. Previous observations at 144 MHz have shown that the cluster exhibits a plethora of diffuse emission, with multiple diffuse sources of uncertain classification because of the lack of spectral and polarimetric observations. MeerKAT multi-frequency observations, centered at 816 MHz and 1.28 GHz, together with archival low-frequency LOFAR observations at 144 MHz have allowed us to shed light on the properties of these sources. The polarization properties and spectral index information let us conclude that the cluster hosts one radio relic, a source with a very steep spectrum, previously classified as candidate relic, and filaments of very steep emission around the tailed radio galaxies identified at low frequencies. The presence of a radio halo is confirmed, and its spectrum shows hints for curvature between 144 MHz ad 1.28 GHz. The polarimetric data in the L-band, together with the model of the gas density derived from X-ray observations are used to constrain the magnetic field in the intracluster medium. We assume a radially symmetric magnetic field model, whose strength declines with the cluster gas density as B(r) ~ n_e(r)^0.5, and normalize its strength within R_500. We find that B_500=1 muG best explains the Faraday depth properties of the cluster, though the detection of sources close to the cluster center would be crucial to discriminate among different values. We conclude that the cluster Abell 2034 shows diffuse emission with complex morphologies that do not follow the historical categories of halos and relics. Deep multi-frequency and polarimetric observations are fundamental to understand their origin.
Comments16 pages, accepted by A&A
