Bringing faint active galactic nuclei (AGNs) to light: a view from large-scale cosmological simulations
Bringing faint active galactic nuclei (AGNs) to light: a view from large-scale cosmological simulations
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揭示微弱的活动星系核（AGN）：大规模宇宙学模拟的视角
DOI：
10.1093/mnras/stab2863
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发表时间：
2021
影响因子：
4.8
通讯作者：
Civano, Francesca
中科院分区：
文献类型：
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作者：
Schirra, Adrian P;Habouzit, Mélanie;Klessen, Ralf S;Fornasini, Francesca;Nelson, Dylan;Pillepich, Annalisa;Anglés-Alcázar, Daniel;Davé, Romeel;Civano, Francesca
X射线设施的灵敏度和我们探测较暗的活动星系核（AGN）的能力将随着即将到来的雅典娜使命和AXIS和Lynx概念飞行任务而增加，从而提高我们对X射线双星主导的光度制度中的超大质量黑洞（BH）的理解。我们分析了Illustris、TNG 100、EAGLE和SIMBA宇宙学模拟中暗活动星系核的总体情况，发现它们的宿主星系的性质在不同的模拟中是不同的。在Illustris和EAGLE中，微弱的活动星系核由位于低质量恒星形成星系中的低质量黑洞提供动力。在TNG 100和SIMBA中，它们大多与淬灭大质量星系中更大质量的BH有关。我们模拟了模拟星系的X射线双星（XRB）的布居，发现AGN经常主导星系AGN + XRB的硬X射线光度atz> 2，而XRB主导在一些模拟atz< 2。无论是活动星系核还是XRB辐射在恒星形成和淬灭星系中占主导地位，这取决于模拟结果。模拟中的这些差异可以用来区分未来高分辨率X射线观测的星系形成模型。我们比较了模拟的微弱活动星系核宿主星系的光度观测的堆叠星系从钱德拉。我们的比较表明，模拟后处理与我们的X射线模型往往高估了活动星系核+ XRB的X射线光度，光度可以强烈影响活动星系核的遮蔽。一些模拟揭示了AGN作为恒星质量函数的清晰趋势（例如，大质量星系中的星系光度下降），这在观测中并不明显。
The sensitivity of X-ray facilities and our ability to detect fainter active galactic nuclei (AGNs) will increase with the upcoming Athena mission and the AXIS and Lynx concept missions, thus improving our understanding of supermassive black holes (BHs) in a luminosity regime that can be dominated by X-ray binaries. We analyse the population of faint AGNs () in the Illustris, TNG100, EAGLE, and SIMBA cosmological simulations, and find that the properties of their host galaxies vary from one simulation to another. In Illustris and EAGLE, faint AGNs are powered by low-mass BHs located in low-mass star-forming galaxies. In TNG100 and SIMBA, they are mostly associated with more massive BHs in quenched massive galaxies. We model the X-ray binary (XRB) populations of the simulated galaxies, and find that AGNs often dominate the galaxy AGN + XRB hard X-ray luminosity atz> 2, while XRBs dominate in some simulations atz< 2. Whether the AGN or XRB emission dominates in star-forming and quenched galaxies depends on the simulations. These differences in simulations can be used to discriminate between galaxy formation models with future high-resolution X-ray observations. We compare the luminosity of simulated faint AGN host galaxies to observations of stacked galaxies fromChandra. Our comparison indicates that the simulations post-processed with our X-ray modelling tend to overestimate the AGN + XRB X-ray luminosity; luminosity that can be strongly affected by AGN obscuration. Some simulations reveal clear AGN trends as a function of stellar mass (e.g. galaxy luminosity drop in massive galaxies), which are not apparent in the observations.