发表机构
Christ University; INAF-IASF; University of Science and Technology of China（克里斯大学; 意大利国家天体物理研究所-帕勒莫天文台; 中国科学技术大学）
机构由 AI 辅助整理，请以论文原文为准。AI 中文总结
本研究通过15年X射线数据揭示NGC 7582的变脸行为源于质量吸积变化，并建立冕层与宽线区的物理联系，为理解CLAGN提供关键机制。
AI 中文摘要
变脸活动星系核（CLAGN）是活动星系核（AGN）的一个子类，其在光学/紫外和X射线波段表现出光谱状态转变，时间尺度从几天到几年不等。在本工作中，我们研究了来自{\it Suzaku}、{\it XMM-Newton}和{\it NuSTAR}的CLAGN NGC 7582的十五年X射线数据，以理解CL行为的起源。我们的研究揭示，视线方向的遮蔽（氢柱密度，$N_H$）与失败风（failed wind）情景相关。质量吸积的变化是唯一能同时解释失败风和CL行为起源的关键因素。NGC 7582中的质量吸积行为类似于黑洞双星的硬光谱状态。此外，在NGC 7582中观测到的CL时间尺度可以通过宽线区（BLR）的动力学时间尺度或对于黑洞质量为$5.3^{+0.5}_{-0.3} \times 10^7 M_\odot$的冕层边界层的粘性和热时间尺度来解释。因此，我们的研究突显了冕层与宽线区之间的直接物理联系，这可能是CL行为的潜在驱动因素。
英文摘要
Changing Look Active Galactic Nuclei (CLAGN) are a subclass of AGN that exhibit spectral state transitions in both optical/UV and X-ray bands on timescales of days to years. In this work, we studied fifteen years of X-ray data of the CLAGN NGC 7582 taken from {\it Suzaku}, {\it XMM-Newton}, and {\it NuSTAR} to understand the origin of the CL behavior. Our study reveals that the obscuration (Hydrogen column density, $N_H$) along the line of sight is associated with the failed wind scenario. The variation in mass accretion is the key that can solely explain the origin of both the failed wind and CL behavior. The mass accretion behavior in NGC 7582 resembles the hard spectral state of black hole binaries. Furthermore, the observed CL timescales in NGC 7582 can be explained either by the dynamical timescale at the BLR or by viscous and thermal timescales at the boundary layer of the corona for a black hole mass of $5.3^{+0.5}_{-0.3} \times 10^7 M_\odot$. Our study thus highlights a direct physical link between the corona and the BLR, which may be potential drivers of the CL behavior.
Comments17 pages, 7 figures, submitted, comments welcome
