Toward more robust numerical and observational comparisons

进行更稳健的数值和观察比较

• 批准号: RGPIN-2019-06829
• 负责人: Thacker, Robert
• 金额: $ 1.75万
• 依托单位: Saint Mary's University
• 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=743986
• 关键词: Toward; more; robust; numerical; observational

This proposal lays out a program of research designed to help us further understand both the applicability and limitations of using numerical simulations of galaxy formation to help explain observational results from both a phenomenological and statistical perspective. This investigation theme is motivated by the next generation of large scale surveys that will operate in the 2020s, such as the Large Synoptic Survey Telescope and the European Euclid mission (to name but two major projects), that will provide statistical samples of galaxies of exceptional size and fidelity. The proposal is primarily focused on further understanding three key components of simulations: Firstly the variance of galaxy properties produced by chaos-like evolution in simulations, an issue that is growing in concern within the community. Secondly an examination of evolutionary and environmental issues within observationally derived correlations of properties of galaxies, such as the star formation rate (SFR) of a galaxy versus the inferred black hole accretion rate (BHAR), and thirdly an examination of whether the evolution of isolated dwarf system is sufficiently simple to allow star formation models to be directly constrained. All simulation work will be conducted using the `state-of-the-art' GIZMO code, with a limited amount of development necessary to add new computational techniques. The studies of chaos will involve resimulating galaxies multiple times under varying situations to see how the level of chaos-like evolution decomposes via two separate potential channels, namely halo, and disk evolution. The disk evolution part of the analysis will be conducted using a newly developed algorithm that provides a simple measure of the local level of mixing. A complementary investigation will examine how different models of the energy return from star formation, `feedback', produce different levels of chaos, as current investigations provide contradictory results on the addition of more complex physics. The research theme focused on understanding the SFR-BHAR correlation will first examine a suite of 300 simulated clusters to focus on environmental impacts on the activity of nuclear accretion in galaxies and then move on to a larger simulation project that precisely constrains the build-up of mass in galaxy halos to determine if that can be used as means to better understand observed correlations. The star formation model constraint project will also use a suite of simulated galaxy models to conduct a sensitivity analysis of the star formation efficiency and various feedback parameters versus the epoch of cosmic reionization. The research will be supported by an award winning outreach portfolio that will be broadened to build a collaboration with Mi'kmaq artist, Melissa Sue Labrador, who is especially interested in the cosmic evolution and relating this to indigenous ways of knowing. The PI & research group will explore with Labrador in the spirit of "Two-eyed seeing."

该提案提出了一项研究计划，旨在帮助我们进一步了解使用星系形成数值模拟的适用性和局限性，以帮助从现象学和统计学的角度解释观测结果。这一调查主题的灵感来自于将于 2020 年代运行的下一代大型巡天，例如大型综合巡天望远镜和欧洲欧几里得任务（仅举两个主要项目），这些项目将提供特殊星系的统计样本尺寸和保真度。 该提案主要侧重于进一步理解模拟的三个关键组成部分：首先，模拟中的混沌演化所产生的星系特性的方差，这是社区内日益关注的问题。其次，在观测得出的星系属性相关性中检查进化和环境问题，例如星系的恒星形成率（SFR）与推断的黑洞吸积率（BHAR），第三，检查孤立的星系的演化是否矮星系统足够简单，可以直接约束恒星形成模型。 所有模拟工作都将使用“最先进的”GIZMO 代码进行，并需要进行有限的开发来添加新的计算技术。对混沌的研究将涉及在不同情况下多次重新模拟星系，以了解类混沌演化的水平如何通过两个独立的潜在通道（即晕和盘演化）分解。分析的磁盘演化部分将使用新开发的算法进行，该算法提供了局部混合水平的简单测量。一项补充研究将研究恒星形成过程中能量返回的不同模型（“反馈”）如何产生不同程度的混乱，因为当前的研究在增加更复杂的物理学方面提供了相互矛盾的结果。研究主题侧重于了解 SFR-BHAR 相关性，将首先检查一组 300 个模拟星团，重点关注环境对星系核吸积活动的影响，然后转向更大的模拟项目，精确限制星系核吸积的积累。星系晕中的质量以确定是否可以用作更好地理解观测到的相关性的手段。恒星形成模型约束项目还将使用一套模拟星系模型对恒星形成效率和各种反馈参数与宇宙再电离时代进行敏感性分析。这项研究将得到屡获殊荣的外展组合的支持，该组合将扩大到与 Mi'kmaq 艺术家梅丽莎·苏·拉布拉多 (Melissa Sue Labrador) 的合作，她对宇宙演化以及将其与本土认知方式联系起来特别感兴趣。 PI＆研究小组将本着“两只眼睛看到”的精神与拉布拉多一起探索。