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.

位于星系中心的超大质量黑洞（活动星系核，AGN）可以由气体吸积提供燃料，产生极高能量的现象，如吸积气体的发光热盘和相对论等离子体和磁场的强大外流，称为喷流。 观测到的超大质量黑洞和宿主星系的质量之间的关系表明，星系和它们的中心黑洞必须在反馈机制的影响下共同进化，这种反馈机制创造了它们质量的比例。 最近已经认识到，强大的活动星系核驱动的外流直接影响星系的演化，喷流中的动能加热星系的气体并将其从中央隆起区域排出。这反过来又影响星系星星的形成历史，调解宿主星系和中央超大质量黑洞之间的关系，塑造星系光度函数的高光度端。“活动星系核反馈效应”现在经常被纳入星系演化的数值模拟中。然而，关于活动星系核如何与形成和演化的宿主星系及其环境相互作用，包括反馈的时间尺度和能量学，仍然存在重大的不确定性。如果我们要真正理解星系演化和活动星系核活动之间的联系，从而准确地将活动星系核反馈效应纳入星系形成和演化模型，解决这些不确定性是很重要的。这个问题已被确定为天文学和天体物理学的一个关键问题，在加拿大和美国最近的十年调查。 我的长期目标是了解由于扩展射电源而在宿主星系中沉积能量的物理过程，包括空间尺度，时间尺度和总能量。我们的短期目标是调查紧凑的无线电源，以探测喷流和它们的星际介质（ISM）之间的相互作用在次千秒差距到千秒差距的尺度。这些射电源与ISM的大小很好地匹配，无论是积极的还是消极的意义上，都应该对宿主星系的星星形成产生最大的影响。我以前的工作已经表明，在致密射电源的喷流强烈的气体云相互作用，可以触发星星形成在某些情况下，也可以驱动冲击到ISM的热组件。因此，CSS源探测理解射电源反馈所需的时间尺度和能量。这项研究的影响将大大提高我们对星系的形成和演化如何受到超大质量黑洞影响的理解。所要求的资金将为两名研究生和一名本科生在U马尼托巴的夏季研究提供5年的支持。学生将培养团队合作，独立思考，有效沟通和开展一线科学研究所需的技能。