Unveiling the quasar main sequence: illuminating the complexity of active galactic nuclei and their evolution
Swayamtrupta Panda
备注：
Mini Review Article based on the invited talk in Frontiers in Astronomy and Space Sciences: A Decade of Discovery and Advancement - 10th Anniversary Conference. This version matches the published version (19-09-2024)
发表信息：
Frontiers in Astronomy and Space Sciences, 2024, Volume 11, eid 1479874
The Eigenvector 1 schema, or the main sequence of quasars, was introduced as an analogous scheme to the HR diagram that would allow us to understand the more complex, extended sources - active galactic nuclei (AGNs) that harbor accreting supermassive black holes. The study has spanned more than three decades and has advanced our knowledge of the diversity of Type-1 AGNs from both observational and theoretical aspects. The quasar main sequence, in its simplest form, is the plane between the FWHM of the broad H$β$ emission line and the strength of the optical FeII emission to the H$β$. While the former allows the estimation of the black hole mass, the latter enables direct measurement of the metal content and traces the accretion rate of the AGN. Together, they allow us to track the evolution of AGN in terms of the activity of the central nuclei, its effect on the line-emitting regions surrounding the AGN, and their diversity making them suitable distance indicators to study the expansion of our Universe. This mini-review aims to provide (i) a brief history leading up to the present day in the study of the quasar main sequence, (ii) introduce us to the many possibilities to study AGNs with the main sequence as a guiding tool, and (iii) highlight some recent, exciting lines of researches at the frontier of this ever-growing field.
Unveiling the weak radio quasar population at z $\geq$ 4
我们对以$z\geq4$光学识别的高红移类星体为中心的20厘米射电天空空场微弱图像（FIRST）巡天图进行了图像叠加，以揭示这些活动星系核（AGN）中隐藏的$μ$ Jy射电辐射。$2229$光学鉴定活动星系核全样本的中值叠加程序揭示了一个积分通量密度为52 $~μ$ Jy的未分辨点源，信噪比为$\sim10$。我们共同添加的个人图像中心像素，以估计在$1.4~$ GHz的特征单色无线电功率考虑各种值的无线电频谱指数，揭示了无线电人口与$P_\mathrm{1.4GHz}\sim10^{24}~$ W Hz $^{-1}$。假设所有的射电辐射都来自于宿主星系核区的恒星形成（SF）活动，我们得到了特征恒星形成速率的上限，即$\sim4200~$ M $_\odot~$ yr $^{-1}$。FIRST图像的角分辨率不足以区分SF和AGN在这些红移处的射电辐射起源。然而，从文献中的个别来源的属性的比较表明，一个混合的性质是可能的。未来的甚长基线射电干涉测量观测和超深平方公里阵列巡天可望具有足够的灵敏度来探测和分辨宿主星系的中心$1-10~$ kpc区域，从而区分SF和AGN相关的辐射。
Unveiling the Cosmic Dawn with SHARP: Probing extended Lyman-$α$ nebulae in a Universe less than 600 Myr old
INAF-IASF Milano（意大利国家天体物理研究所米兰天文物理研究所）；INAF – Osservatorio Astronomico di Roma（意大利国家天体物理研究所罗马天文台）；Department of Mathematics and Physics, Roma Tre University（罗马三大大学数学与物理系）；INAF–OAT, Osservatorio Astronomico di Trieste（意大利国家天体物理研究所的里雅斯特天文台）
Multi-phase AGN-driven outflow in the NLSy1 IRAS 17020+4544. Unveiling dual-feedback and an energy-conserving ionized outflow with MEGARA/GTC integral field spectroscopy
Universidad Complutense de Madrid（马德里康普顿斯大学）；Instituto de Física de Partículas y del Cosmos (IPARCOS)（粒子与宇宙物理研究所（IPARCOS））；Universidad Nacional Autónoma de México（墨西哥国立自治大学）；Finnish Centre for Astronomy with ESO (FINCA)（芬兰欧洲南方天文台天文学中心（FINCA））；University of Turku（图尔库大学）；Universidad de Guanajuato（瓜纳华托大学）；Instituto Nacional de Astrofísica, Óptica y Electrónica（国家天文学、光学和电子学研究所）；Universidad Nacional Autónoma de Nicaragua（尼加拉瓜国立自治大学）；Centro de Investigación de Astrofísica y Ciencias Espaciales (CIACE)（天体物理学与空间科学研究中心（CIACE））
Unveiling the population of massive quenched galaxies at $z\ge2$ in the COLIBRE simulations - II. The role of AGN feedback and environment on their emergence
International Centre for Radio Astronomy Research (ICRAR), The University of Western Australia（西澳大利亚大学国际射电天文研究中心）；ARC Centre for All-Sky Astrophysics in 3 Dimensions (ASTRO 3D)（ARC三维全天空天体物理中心）；DARK, Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；Dipartimento di Fisica G. Occhialini, Università degli Studi di Milano Bicocca（米兰比可卡大学G. Occhialini物理系）；Institute for Computational Cosmology, Department of Physics, University of Durham（杜伦大学物理学院计算宇宙学研究所）；Leiden Observatory, Leiden University（莱顿大学莱顿天文台）；Centre for Astrophysics and Supercomputing, Swinburne University of Technology（斯威本科技大学天体物理学与超级计算中心）
