BALSims: a Spectral Synthesis Approach to Understanding Broad Absorption Line Quasar Outflows

BALSims：一种了解宽吸收线类星体流出的光谱合成方法

• 批准号: 1518382
• 负责人: Karen Leighly
• 金额: $ 25.06万
• 依托单位: University of Oklahoma Norman Campus
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1518382&HistoricalAwards=false
• 关键词: BALSims; Spectral; Synthesis; Approach; Understanding

A longstanding problem in astrophysics is to understand how galaxies form and develop throughout their lifetimes. Such understanding is necessary to uncover how our Universe evolved and to gain insight into the origin of our own Milky Way Galaxy. One important aspect of understanding galaxy formation and evolution is to study supermassive black holes at the centers of galaxies and how these black holes interact with their host galaxies. Observational evidence suggests that black holes and galaxies evolve together. This evidence includes the tightness of the correlation between the black hole mass and galaxy bulge properties and the similar history of black hole growth and star formation. This evidence is supported by theoretical arguments. Black holes in their active phase emit more than enough energy to unbind the host galaxies' bulge, and in their non-active phase should be present in the centers of most present-day galaxies. As a consequence, many models for galaxy formation include a unspecified process by which a fraction of the energy released in the region surrounding the black hole contributes to the galaxy formation environment. This interaction is generically known as "feedback," and the mechanism by which the black hole acts on the host galaxy remains a mystery. This project uses a novel spectral synthesis and statistical approach to build the tools needed to constrain the key parameter characterizing one type of feedback.In addition, the project activities will directly contribute to the training of young scientists, including undergraduate students, in techniques of spectral and statistical analysis. The PI will develop and teach a course, directed toward advanced undergraduate and graduate students, on machine learning and statistical methods, some of which will be used in this project. The PI will bring the results of this research to the citizens of Oklahoma through participation in the OU speakers program.This research effort will constrain the key parameter characterizing quasar mode feedback: the ratio of the kinetic luminosity to bolometric luminosity, in the SDSS broad absorption line quasars as a whole. In addition, the carefully-phased research program addresses related scientific questions at each check point. These include the location and nature of feedback interactions, a search for and evaluation of absorption-line spectral diagnostics, and constraints of key outflow physical parameters, including column density, ionization parameter, and covering fraction.This research project will yield insights into the physics of quasar outflows, and measurements of key parameters that will be valuable to a wide variety of researchers. These include scientists who are interested in on-going interactions potentially occurring in infrared-loud quasars, data analysts who use spectral diagnostics to infer physical conditions from spectra of individual objects, and theorists who need observational constraints to develop their hydromagnetic wind models, as well as providing an assessment of the viability of quasar-mode feedback for galaxy evolution models.

天体物理学的一个长期问题是了解星系在其一生中是如何形成和发展的。 这样的理解对于揭示我们的宇宙是如何演化的以及深入了解我们银河系的起源是必要的。 理解星系形成和演化的一个重要方面是研究星系中心的超大质量黑洞以及这些黑洞如何与它们的宿主星系相互作用。 观测证据表明，黑洞和星系是一起演化的。 这些证据包括黑洞质量和星系核球性质之间的紧密相关性，以及黑洞生长和星星形成的相似历史。 这一证据得到了理论论证的支持。 黑洞在活跃阶段释放出的能量足以使宿主星系的膨胀解除束缚，而在非活跃阶段应该存在于大多数现代星系的中心。 因此，许多星系形成的模型包括一个未指明的过程，其中黑洞周围区域释放的一小部分能量有助于星系形成环境。 这种相互作用通常被称为“反馈”，黑洞作用于宿主星系的机制仍然是一个谜。 该项目使用一种新的光谱合成和统计方法来建立所需的工具，以限制表征一类反馈的关键参数，此外，项目活动将直接有助于培训包括本科生在内的年轻科学家掌握光谱和统计分析技术。 PI将开发和教授一门针对高年级本科生和研究生的机器学习和统计方法课程，其中一些将用于本项目。 PI将通过参与“演讲者计划”把这项研究的结果带给俄克拉荷马州的公民。这项研究工作将限制SDSS宽吸收线类星体整体上表征类星体模式反馈的关键参数：动力学光度与测热光度之比。 此外，精心分阶段进行的研究计划在每个检查点解决相关的科学问题。 这些包括反馈相互作用的位置和性质，对吸收线光谱诊断的搜索和评估，以及关键流出物理参数的约束，包括柱密度，电离参数和覆盖分数。 这些科学家包括对可能发生在红外大声类星体中的持续相互作用感兴趣的科学家，使用光谱诊断从单个物体的光谱推断物理条件的数据分析师，以及需要观测约束来开发其磁流体风模型的理论家，以及为星系演化模型提供类星体模式反馈的可行性评估。

项目成果

The Physical Properties of Low-redshift FeLoBAL Quasars. III. The Location and Geometry of the Outflows

• DOI: 10.3847/1538-4357/ac854c
• 发表时间: 2022-08
• 期刊: The Astrophysical Journal
• 作者: Hyunseop 현섭 Choi 최;K. Leighly;C. Dabbieri;D. Terndrup;S. Gallagher;G. Richards

The Physical Properties of Low-redshift FeLoBAL Quasars. I. Spectral-synthesis Analysis of the Broad Absorption-line (BAL) Outflows Using SimBAL

• DOI: 10.3847/1538-4357/ac61d9
• 发表时间: 2022-03
• 期刊: The Astrophysical Journal
• 作者: Hyunseop 현섭 Choi 최;K. Leighly;D. Terndrup;C. Dabbieri;S. Gallagher;G. Richards

The Physical Properties of Low-redshift FeLoBAL Quasars. II. The Rest-frame Optical Emission Line Properties

• DOI: 10.3847/1538-4357/ac7e50
• 发表时间: 2022-05
• 期刊: The Astrophysical Journal
• 作者: K. Leighly;Hyunseop Choi;Cora DeFrancesco;J. Voelker;D. Terndrup;S. Gallagher;G. Richards