为理解超爱丁顿吸积的本质，我们必须同时探究直接从吸积流发出的辐射及其对周围环境的影响。本文测试了能否将超亮X射线源（ULX）周围空间分辨的电离星云的光学线发射作为其X射线光度的代理指标。我们选取ULX NGC 6946 X-1及其星云MF16作为测试案例。通过研究星云光学线发射对假定辐照的响应，我们可以推断吸积流的紫外或X射线辐射被光学厚风准直的程度——这类风似乎普遍与ULX相关。我们发现，星云对致密紫外辐射高度敏感，但对硬X射线基本不敏感。因此，我们量化软、硬X射线束流程度的尝试，强烈依赖于星云中心ULX的紫外光度。研究表明，无法通过星云反馈来断定这类源不存在硬X射线的几何束流效应。
英文摘要：
In order to understand the nature of super-Eddington accretion we must explore both the emission emerging directly from the inflow and its impact on the surroundings. In this paper we test whether we can use the optical line emission of spatially resolved, ionized nebulae around ultraluminous X-ray sources (ULXs) as a proxy for their X-ray luminosity. We choose the ULX NGC 6946 X-1 and its nebula, MF16, as a test case. By studying how the nebular optical line emission responds to assumed irradiation, we can infer the degree to which we require the UV or X-ray emission from the inflow to be collimated by optically thick winds seemingly ubiquitously associated with ULXs. We find that the nebula is highly sensitive to compact UV emission but mostly insensitive to hard X-rays. Our attempts to quantify the beaming of the soft and hard X-rays therefore strongly depends on the UV luminosity of the ULX in the center of the nebula. We find that it is not possible to conclude a lack of geometrical beaming of hard X-rays from such sources via nebula feedback.
On the Magnetic Fields, Beaming Fractions, and Fastness Parameters of Pulsating Ultra-Luminous X-Ray Sources
脉动超亮X射线源（PULX）的发现表明，中子星可能是常见的超亮X射线源（ULX）的人口，虽然大多数人口成员目前缺乏脉动。这些系统很可能是中子星的宿主，它们以超爱丁顿（超临界）速率从高质量X射线双星中的大质量伴星中吸积质量。考虑到超临界吸积流的球化、X射线发射的聚束以及强磁场中散射截面的减小，我们推断了PULX M82 X-2、ULX NGC 5907、ULX NGC 7793 P13、ULX NGC 7793 P14、ULX NGC 7793 P15、ULX NGC 7793 P16、ULX NGC 7793 P17、ULX NGC 7793 P18和ULX NGC 7793 P17 NGC 300 ULX 1、M51 ULX-7、NGC 1313 X-2和Swift J0243.6+6124，它们来自一组基于不同自旋和光度状态的各种组合的条件。使用所观察到的自旋率下的临界光度条件下，我们估计的表面场强度在$\sim 10^{11}-10^{13}\,{\rm G}$范围内的所有PULX。在一般情况下，我们的分析结果在亚临界光度条件下表明表面场强度在$\sim 10^{11}-10^{15}\,{\rm G}$范围内。我们认为，PULX不需要磁强度的表面偶极场，如果考虑到波束，但该领域是强大的，足以让中子星在ULX磁通道的吸积流超临界吸积盘。
Forgotten treasures in the HST/FOC UV imaging polarimetric archives of active galactic nuclei. I. Pipeline and benchmarking against NGC~1068 and exploring IC~5063
Differential Sensitivity of the KM3NeT/ARCA detector to a diffuse neutrino flux and to point-like source emission: exploring the case of the Starburst Galaxies
X-ray polarization of the Compton-thin Seyfert galaxy NGC 5506 with IXPE
Università degli Studi Roma Tre（罗马第三大学）；Istituto Nazionale di Fisica Nucleare, Sezione di Roma “Tor Vergata”（意大利国家核物理研究所罗马“托尔维加塔”分部）；NASA Marshall Space Flight Center（美国国家航空航天局马歇尔太空飞行中心）；Agenzia Spaziale Italiana（意大利航天局）；INAF - Osservatorio astronomico di Roma（意大利国家天体物理研究所罗马天文台）；Clemson University（克莱姆森大学）；INAF-Osservatorio Astronomico di Brera（意大利国家天体物理研究所布里埃拉天文台）
