论文标题
强大而孤独的：3C 297是一个高红移化石群吗？
Powerful yet lonely: Is 3C 297 a high-redshift fossil group?
论文作者
论文摘要
高红移（Z = 1.408）的环境，强大的无线电路线3C 297具有星系群的几个独特特征。其中，Chandra X射线观察结果揭示了热气的特征性光环。此外，使用非常大的阵列（VLA）获得的无线电图显示了一个明亮的热点，它是由3C 297与环境的AGN射流相互作用所产生的。在X射线图像中，检测到与西北无线电叶的发射相位，并在无线电热点的位置达到峰值。使用我们的新Chandra数据观察到的扩展，复杂的X射线发射与其无线电结构无关。尽管具有星系群集的属性，但从39个新的靶标的3C 297个新的靶标光谱中却没有鉴定出伴随星系，该光谱使用Gemini多对象光谱仪获得。没有与3C 297相同的距离确定红移的19个星系。对3C 297的新双子座光谱的光谱分析揭示了一个孤立的II型Radio-Loud AGN。我们还检测到[O II]（3728）的线扩展，FWHM约为1700 km/s，可能的线偏移高达500-600 km/s。我们假设3C 297的宿主星系是一个化石组，其中大多数恒星质量已合并为一个对象，留下了X射线光环。
The environment of the high-redshift (z=1.408), powerful radio-loud galaxy 3C 297 has several distinctive features of a galaxy cluster. Among them, a characteristic halo of hot gas revealed by Chandra X-ray observations. In addition, a radio map obtained with the Very Large Array (VLA) shows a bright hotspot in the northwestern direction, created by the interaction of the AGN jet arising from 3C 297 with its environment. In the X-ray images, emission cospatial with the northwestern radio lobe is detected, and peaks at the position of the radio hotspot. The extended, complex X-ray emission observed with our new Chandra data is largely unrelated to its radio structure. Despite having attributes of a galaxy cluster, no companion galaxies have been identified from 39 new spectra of neighboring targets of 3C 297 obtained with the Gemini Multi-Object Spectrograph. None of the 19 galaxies for which a redshift was determined lies at the same distance as 3C 297. The optical spectral analysis of the new Gemini spectrum of 3C 297 reveals an isolated Type-II radio-loud AGN. We also detected line broadening in [O II](3728) with a FWHM about 1700 km/s and possible line shifts of up to 500-600 km/s. We postulate that the host galaxy of 3C 297 is a fossil group, in which most of the stellar mass has merged into a single object, leaving behind an X-ray halo.
