我们提出了河外偶发性雨燕调查（ExSeSS），提供了一个新的定义明确的样本，从使用雨燕X射线望远镜进行的观测。ExSeSS样本包括在中等（1-2 keV）、硬（2-10 keV）或总（0.3-10 keV）能带中检测到的79，342个源，覆盖天空2086.6 deg $^{2}$，通量范围为$f_\mathrm{0.3-10keV}\sim10^{-15}-10^{-10}$ erg s $^{-1}$ cm $^{-2}$。使用新的ExSeSS样品，我们提出了测量的微分数计数的X射线源作为2-10千电子伏通量的函数，跟踪人口的活动星系核（AGN）在以前未探索的制度。我们发现，考虑到视线吸收列密度的微分计数测量的影响，是至关重要的，以获得与以前的结果一致。在硬带，我们得到了很好的协议之间的ExSeSS测量和以前的，更高的能量数据从NuSTAR和斯威夫特/BAT时，考虑到不同的列密度的ExSeSS样品以及X射线光谱参数的每个样品，我们正在比较。我们还发现ExSeSS测量和活动星系核人口合成模型之间的差异，表明在这个通量范围内的活动星系核人口的属性的变化，这是不完全描述当前的模型在这些能量，暗示在一个更大的，适度模糊的人口在低红移（$z\lesssim0.2$）的模型目前没有考虑。
英文摘要：
We present the Extragalactic Serendipitous Swift Survey (ExSeSS), providing a new well-defined sample constructed from the observations performed using the Swift X-ray Telescope. The ExSeSS sample consists of 79,342 sources detected in the medium (1-2 keV), hard (2-10 keV) or total (0.3-10 keV) energy bands, covering 2086.6 deg$^{2}$ of sky across a flux range of $f_\mathrm{0.3-10keV}\sim10^{-15}-10^{-10}$ erg s$^{-1}$ cm$^{-2}$. Using the new ExSeSS sample we present measurements of the differential number counts of X-ray sources as a function of 2-10 keV flux that trace the population of Active Galactic Nuclei (AGN) in a previously unexplored regime. We find that taking the line-of-sight absorption column density into account has an effect on the differential number count measurements and is vital to obtain agreement with previous results. In the hard band, we obtain a good agreement between the ExSeSS measurements and previous, higher energy data from NuSTAR and Swift/BAT when taking into account the varying column density of the ExSeSS sample as well as the X-ray spectral parameters of each of the samples we are comparing to. We also find discrepancies between the ExSeSS measurements and AGN population synthesis models, indicating a change in the properties of the AGN population over this flux range that is not fully described by current models at these energies, hinting at a larger, moderately obscured population at low redshifts ($z\lesssim0.2$) that the models are not currently taking into account.
Is the Peculiar Galactic Center Transient Swift J174610.4-290018 A Nova Outburst?
School of Astronomy and Space Science, Nanjing University（南京大学天文与空间科学学院）；Key Laboratory of Modern Astronomy and Astrophysics (Nanjing University), Ministry of Education（南京大学现代天文与天体物理教育部重点实验室）；Institute of Science and Technology for Deep Space Exploration, Suzhou Campus, Nanjing University（南京大学苏州校区深空探测科学与技术研究院）
Comprehensive X-ray Observations of the Exceptional Ultra-long X-ray and Gamma-ray Transient GRB 250702B with Swift, NuSTAR, and Chandra: Insights from the X-ray Afterglow Properties
Carnegie Mellon University（卡内基梅隆大学）；The Open University of Israel（以色列开放大学）；The Pennsylvania State University（宾夕法尼亚州立大学）；NASA Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；Center for Research and Exploration in Space Science and Technology, NASA/GSFC（空间科学与技术研究探索中心（NASA/GSFC））；The Catholic University of America（美利坚天主教大学）；The George Washington University（乔治华盛顿大学）；Syracuse University（雪城大学）；University of North Carolina at Chapel Hill（北卡罗来纳大学教堂山分校）；Ludwig-Maximilians-Universität München（慕尼黑大学）；Gran Sasso Science Institute (GSSI)（格兰萨索科学研究所）；California Institute of Technology（加州理工学院）；Northwestern University（西北大学）
Representation Learning for Time-Domain High-Energy Astrophysics: Discovery of Extragalactic Fast X-ray Transient XRT 200515
Institute for Computational and Mathematical Engineering, Stanford University（斯坦福大学计算与数学工程研究所）；University of Cambridge（剑桥大学）；Center for Astrophysics | Harvard & Smithsonian（哈佛-史密森天体物理中心）；INAF – Osservatorio Astrofisico di Torino（意大利国家天体物理研究所都灵天文台）；The University of Sydney（悉尼大学）
