标题： 在最深的钱德拉巡天中寻找最高红移的双活跃星系核 显示英文标题

标题： Searching for the Highest-z Dual AGN in the Deepest Chandra Surveys

摘要： 我们对来自公开的深场钱德拉（Chandra）数据中的62个高红移（$2.5 < z < 3.5$）X射线源进行了分析，以寻找双活跃星系核（AGN）。我们的目标是量化高红移宇宙中双AGN的频率，这与黑洞合并的时间尺度以及低频引力波探测率有关。 我们使用BAYMAX工具（一种计算贝叶斯因子的分析工具）来分析每个X射线源，该工具可以判断给定的档案中的钱德拉AGN更可能是单一还是双重点源。 我们没有发现样本中任何单个源存在强烈证据表明存在双AGN。 然后，我们将测量的贝叶斯因子分布与完全由单点源组成的样本所预期的分布进行比较，以提高我们对样本中双AGN的敏感度，但仍然没有发现观测样本分布中有双AGN的证据。 尽管我们的分析利用了研究用的最大的高红移（$z$）X射线点源钱德拉目录之一，但结果仍受到通过钱德拉观测到的源数量有限以及检测到的源通常计数率较低的限制。 我们的未检测结果使我们能够对X射线双AGN的比例设定一个上限，即在（$2.5<z<3.5$）范围内不超过4.8%。 要在X射线波段上显著扩展这些结果，需要未来的巡天覆盖更大的天空区域，并延伸至比钱德拉可能实现的更暗的流量。 我们在本文中展示了AXIS任务概念在这方面的能力。 显示英文摘要

摘要： We present an analysis searching for dual AGN among 62 high-redshift ($2.5 < z < 3.5$) X-ray sources selected from publicly available deep Chandra fields. We aim to quantify the frequency of dual AGN in the high-redshift Universe, which holds implications for black hole merger timescales and low-frequency gravitational wave detection rates. We analyze each X-ray source using BAYMAX, an analysis tool that calculates the Bayes factor for whether a given archival Chandra AGN is more likely a single or dual point source. We find no strong evidence for dual AGN in any individual source in our sample. We then increase our sensitivity to search for dual AGN across the sample by comparing our measured distribution of Bayes factors to that expected from a sample composed entirely of single point sources, and again find no evidence for dual AGN in the observed sample distribution. Although our analysis utilizes one of the largest Chandra catalogs of high-$z$ X-ray point sources available to study, the findings remain limited by the modest number of sources observed at the highest spatial resolution with Chandra and the typical count rates of the detected sources. Our non-detection allows us to place an upper-limit on the X-ray dual AGN fraction between $2.5<z<3.5$ of 4.8\%. Expanding substantially on these results at X-ray wavelengths will require future surveys spanning larger sky areas and extending to fainter fluxes than has been possible with Chandra. We illustrate the potential of the AXIS mission concept in this regard.