The Origin and Evolution of Extragalactic Radio Sources and their Impact on Galaxy Formation and Evolution

河外射电源的起源和演化及其对星系形成和演化的影响

• 批准号: RGPIN-2022-04128
• 负责人: ODea, Christopher
• 金额: $ 2.04万
• 依托单位: University of Manitoba
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=763058
• 关键词: Origin; Evolution; Extragalactic; Radio; Sources

Supermassive black holes located in the center of a galaxy (an Active Galactic Nucleus, AGN) can be fueled by the accretion of gas, producing extremely energetic phenomenon such as luminous hot disks of accreting gas and powerful outflows of relativistic plasma and magnetic fields, called jets.  The observed relation between mass of the supermassive black hole and the host galaxy  indicates that galaxies and their central black holes must co-evolve under the influence of a feedback mechanism which creates the proportionality in their masses.  It has been recently recognized that powerful AGN-driven outflows directly affect the evolution of galaxies, with the kinetic energy in the jets heating the galaxy's gas and expelling it from the central bulge regions. This in turn influences galaxies star formation histories, mediating the relationship between host galaxy and central supermassive black hole shaping the high luminosity end of the galaxy luminosity function. The "AGN feedback effect" is now routinely incorporated into numerical simulations of galaxy evolution. However, major uncertainties remain about how AGN interact with the forming and evolving host galaxies and their environments, including the time scales and energetics of the feedback. It is important to resolve these uncertainties if we are to truly understand the links between galaxy evolution and AGN activity, and thereby accurately incorporate the AGN feedback effect into galaxy formation and evolution models. This question has been identified as a critical issue for astronomy and astrophysics by the most recent decadal surveys in both Canada and the USA. My long term goals are to understand the physical processes through which energy is deposited in the host galaxy due to the expanding radio source, including the spatial scales, time scales, and total energy. Our short term goals for this proposal are to investigate compact radio sources to probe interactions between jets and their interstellar medium (ISM) on sub-kpc to kpc scales. These radio sources are well matched to the size of the ISM and should have maximum impact on the star formation of the host galaxy in either a positive or negative sense. My previous work has shown that the jets in compact radio sources interact strongly with gas clouds, can trigger star formation in some cases, and can also drive shocks into the hot component of the ISM. Thus, the CSS sources probe the time scales and energetics which are needed to understand radio source feedback. The impact of this research will be to greatly improve our understanding of how the formation and evolution of galaxies is affected by their supermassive black holes. The requested funding will provide support for two graduate students and summer research for an undergraduate at U Manitoba for 5 years. The students will develop the skills necessary to work in teams, think independently, communicate effectively, and carry out front-line scientific research.

位于星系中心（活跃的银河核，AGN）的超质量黑洞可以通过气体的积聚来侵蚀，从而产生极具能量的现象，例如接受气体的发光热磁盘和相对性的等离子体和磁场的强大出口，称为Jets。观察到的超质量黑洞与宿主星系之间的关系表明，星系及其中央黑洞必须在反馈机制的影响下共同进化，从而在其质量中产生了比例。最近已经认识到，强大的AGN驱动插座直接影响星系的演变，喷气机中的动能加热了银河系的气体并将其从中央凸起区域排出。反过来，这影响了星系星的形成历史，介导了宿主星系与中央超大质量黑洞之间的关系，从而塑造了星系光度函数的高光度末端。现在，“ AGN反馈效应”通常被纳入星系进化的数值模拟中。但是，关于AGN如何与形成和不断发展的宿主星系及其环境（包括时间尺度和反馈的能量学）相互作用的主要不确定性仍然存在。如果我们要真正了解星系演化与AGN活性之间的联系，从而将AGN反馈效应纳入星系形成和进化模型，那么解决这些不确定性很重要。加拿大和美国的最新衰落调查已将这个问题确定为天文学和天体物理学的关键问题。我的长期目标是了解由于无线电源的扩展，包括空间尺度，时间尺度和总能量，能量沉积在宿主星系中的物理过程。该提案的短期目标是研究紧凑型无线电来源，以证明喷气机与其星际介质（ISM）在Sub-KPC上与KPC量表之间的相互作用。这些无线电来源与ISM的大小相匹配，并且应以正面或负面的方式对宿主星系的恒星形成产生最大影响。我以前的工作表明，紧凑型无线电源中的喷气机与气云强烈相互作用，在某些情况下会触发恒星形成，并且还可以将冲击驱动到ISM的热点。这是CSS来源探测了了解无线电源反馈所需的时间尺度和能量学。这项研究的影响将大大改善我们对星系的形成和发展如何受其超大质量黑洞影响的理解。要求的资金将为两名研究生提供支持，并为U曼尼托巴省的本科生提供5年的夏季研究。学生将发展团队合作，独立思考，有效沟通并进行一线科学研究所需的技能。