The Broad Line Region of Active Galactic Nuclei is characterized by broad Balmer emission lines in their optical spectra. The broad Balmer emission lines are found to be asymmetric, some blue sided and others red sided in their asymmetry. One of the components behind the asymmetry is thought to be an accretion disk wind. We probe the accretion disk wind using the broad balmer emission line profiles.
This asymmetry of the broad balma emission line profiles is measured in velocity space after a measurement of the line shift at percentiles from 0, in increaments of 10, up to 90. In addition, the Kurtosis Index is obtained at appropriate points of the emission lines' profiles. This study is based on many hundreds of SDSS spectra, starting with low redshift high signal to noise ratio spectra. We also consider a definite number in each bin of their FWHM, in bins of 1000 km/s (atleast 40 per bin), starting from 1000km/s to the very broad emission lines.
We present how strong the asymmetry (by plotting Asymmetry Index as a function of percentile) of the broad/narrow lines (in percent) is, what the Kurtosis $(R20, 80)$ is. We also present what the Asymmetry Index as a function of line width (FWHM), luminosity (V-band), core-radio flux and Ionization Degree.
Key Words: AGN: Accretion Disk, Accretion Disk Wind - Line: Asymmetry, Balmer, Emission, Profiles
Probing the Physical Origin of the Balmer Decrement in the Broad-line Region of Nearby Active Galactic Nuclei via Spectral Variability
Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学科维理天文与天体物理研究所）；Department of Astronomy and Atmospheric Sciences, Kyungpook National University（庆北大学天文与大气科学系）；Department of Astronomy, Yonsei University（延世大学天文系）；Department of Astronomy, School of Physics, Peking University（北京大学物理学院天文系）
ATLAS. II. Extremely High Incidence of Balmer Line Absorption with Predominant Blueshifts in LRDs: Statistical Insights through Comparison with Type 1 AGNs
Institute for Cosmic Ray Research, The University of Tokyo（东京大学宇宙射线研究所）；Department of Physics, Graduate School of Science, The University of Tokyo（东京大学理学研究科物理系）；National Astronomical Observatory of Japan（日本国立天文台）；Astronomical Science Program, Graduate Institute for Advanced Studies, SOKENDAI（SOKENDAI高级研究院天文学科学项目）；Kavli Institute for the Physics and Mathematics of the Universe (WPI), The University of Tokyo（东京大学 Kavli宇宙物理数学研究所（WPI））
An (in)complete NIRSpec census of Balmer absorption in Type 1 AGN -- radiation-driven outflows in little red dots, quasars and variable stars
University of Cambridge（剑桥大学）；Kavli Institute for Cosmology, University of Cambridge（剑桥大学卡弗里宇宙学研究所）；Cavendish Laboratory, University of Cambridge（剑桥大学卡文迪许实验室）；University College London（伦敦大学学院）
Origins of the UV continuum and Balmer emission lines in Little Red Dots: observational validation of dense gas envelope models enshrouding the AGN
Dunlap Institute for Astronomy and Astrophysics（邓普天文学与天体物理研究所）；Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学柯夫利天文学与天体物理研究所）；David A. Dunlap Department of Astronomy and Astrophysics, University of Toronto（多伦多大学大卫·A·邓普普天文学与天体物理学系）；NRC Herzberg（国家研究委员会赫茨伯格研究所）
Balmer Transition Signatures from Gas-Enshrouded, Dust-Poor Active Galactic Nuclei
Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学科维理天文与天体物理研究所）；Department of Astronomy, School of Physics, Peking University（北京大学物理学院天文学系）
Space Telescope Science Institute（太空望远镜科学研究所）；Penn State University（宾夕法尼亚州立大学）；Vanderbilt University（范德堡大学）；Fisk University（菲斯克大学）；Tel Aviv University（特拉维夫大学）
Cosmic Dawn Center (DAWN)（宇宙黎明中心）；Niels Bohr Institute, University of Copenhagen（哥本哈根大学尼尔斯·玻尔研究所）；Institute of Astronomy, University of Cambridge（剑桥大学天文研究所）；University of Oxford（牛津大学）
The Extreme Rarity and Physical Properties of Low-redshift AGNs with Balmer Absorption
The Kavli Institute for Astronomy and Astrophysics, Peking University（北京大学科维理天文与天体物理研究所）；Department of Astronomy, School of Physics, Peking University（北京大学物理学院天文学系）；Max Planck Institute for extraterrestrial Physics（马克斯·普朗克地外物理研究所）
Little Red Dots on FIRE: Exploring the formation and observational signatures of ultra-compact early galaxies
University of Connecticut（康涅狄格大学）；University of Manchester（曼彻斯特大学）；University of Hull（赫尔大学）；J.P. Morgan Securities（摩根大通证券）；Northwestern University（西北大学）；NASA-Goddard Space Flight Center（美国宇航局戈达德太空飞行中心）；University of Zurich（苏黎世大学）
Balmer Absorption Series and Broad Metal Lines in Two Luminous Little Red Dots
Princeton University（普林斯顿大学）；Cosmic Dawn Center (DAWN), Copenhagen, Denmark（哥本哈根宇宙黎明中心（DAWN））；Max-Planck-Institut für Astronomie（马克斯·普朗克天文学研究所）；Swinburne University of Technology（斯威本科技大学）；The Pennsylvania State University（宾夕法尼亚州立大学）
Probing star formation and ISM properties using galaxy disk inclination III: Evolution in dust opacity and clumpiness between redshift 0.0 < z < 0.7 constrained from UV to NIR
The line parameters and ratios as the physical probe of the line emitting regions in AGN
本文讨论了活动星系核（AGN）发射线区（ELR）的物理条件，特别强调了尚未解决的问题，如宽线区（BLR）的分层或光电离不能解释观测到的强光学Fe II发射。在这里，我们使用不同的线通量，以探测ELR的属性，如氢巴耳末线（Ha到He），氦线从两个随后的电离水平（He II 4686和He I 5876）和最强的Fe II线在波长范围4400-5400 nm。我们发现，氢巴耳末和氦线可以用于估计的物理参数的BLR，我们表明，Fe II发射主要是从中间线区域（ILR），这是位于更远离中央连续源比BLR。
OQ~208: A New Fe~II Changing-look Active Galactic Nucleus and Implications for the Nature of the Changing-look Phenomenon
National Astronomical Observatories, Chinese Academy of Sciences（中国科学院国家天文台）；Department of Astronomy, University of California, Berkeley（加州大学伯克利分校天文学系）；School of Astronomy and Space Science, University of Chinese Academy of Sciences（中国科学院大学天文与空间科学学院）；Guangxi Key Laboratory for Relativistic Astrophysics, School of Physical Science and Technology, Guangxi University（广西大学物理科学与技术学院相对论天体物理重点实验室）
Probing Heavily Obscured AGN in Major Galaxy Mergers Using the mm-X-ray Correlation
Pontificia Universidad Católica de Chile（智利天主教 Pontificia 大学）；Universidad de Tarapacá（塔拉帕卡大学）；National Radio Astronomy Observatory（美国国家射电天文台）；University of Virginia（弗吉尼亚大学）；Osaka University（大阪大学）；RIKEN Cluster for Pioneering Research（理化学研究所先锋研究集群）；Clemson University（克莱姆森大学）
Optical spectropolarimetry of extreme H$α$ line profiles in seven active galactic nuclei
Université de Strasbourg, CNRS, Observatoire astronomique de Strasbourg（斯特拉斯堡大学）；Institut d’Astrophysique et de Géophysique, Université de Liège（列日大学天体物理学与地球物理学研究所）；Department of Astronomy and Astrophysics, University of California at Santa Cruz（加州大学圣克鲁斯分校天文学与天体物理系）
The X-Ray Dot: Exotic Dust or a Late-Stage Little Red Dot?
Max-Planck-Institut für Astronomie（马克斯·普朗克天文学研究所）；Center for Astrophysics, Harvard & Smithsonian（哈佛与史密森尼天体物理中心）；Department of Astrophysical Sciences, Princeton University（普林斯顿大学天体物理学系）；Leiden Observatory, Leiden University（莱顿大学莱顿天文台）；Department of Physics, University of Oxford（牛津大学物理系）
No hidden monsters: Probing recently-quenched galaxies for obscured AGN with JWST-PRIMER MIRI and NIRCam
University of Nottingham（诺丁汉大学）；Johns Hopkins University（约翰斯·霍普金斯大学）；Space Telescope Science Institute（太空望远镜科学研究所）；University of Edinburgh（爱丁堡大学）；University of St Andrews（圣安德鲁斯大学）
Probing AGN Feedback in Dwarf Galaxies with Spatially Resolved NIR Coronal Lines from JWST
University of California, Riverside（加州大学河滨分校）；The University of Texas at Austin（德克萨斯大学奥斯汀分校）；Ehime University（爱媛大学）；George Mason University（乔治梅森大学）；California Institute of Technology（加州理工学院）；Steward Observatory, University of Arizona（亚利桑那大学斯图尔德天文台）；University of California, Los Angeles（加州大学洛杉矶分校）
A new sample of Little Red Dots at $z<0.45$ in DESI DR1: Broad Balmer lines, low ionization spectrum and no variability
Institute of Science and Technology Austria（奥地利科学技术研究院）；Department of Astronomy, Columbia University（哥伦比亚大学天文学系）；Department of Physics, Columbia University（哥伦比亚大学物理学系）；MIT Kavli Institute for Astrophysics and Space Research（麻省理工学院卡弗里天体物理与空间研究所）；Center for Astrophysics, Harvard & Smithsonian（哈佛-史密森尼天体物理中心）；Max-Planck-Institut für Astronomie（马克斯·普朗克天文学研究所）
研究通过 DESI 调查发现 z=0.2-0.45 的 8 个 Little Red Dots，其光谱特征类似高红移 LRDs，但缺乏高电离线，且无显著变异性，揭示了低红移 LRDs 的稀有性及可能的活动率降低原因。
