Evolution of barred spiral galaxies and chemical enrichment processes of galaxies and their environment

棒旋星系的演化及星系及其环境的化学富集过程

• 批准号: RGPIN-2018-04586
• 负责人: Martel, Hugo
• 金额: $ 1.75万
• 依托单位: Université Laval
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2019
• 资助国家: 加拿大
• 起止时间: 2019-01-01 至 2020-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=679708
• 关键词: Evolution; barred; spiral; galaxies; chemical

The proposed research program is divided in two separate components. The first component is a numerical study of the formation and evolution of barred spiral galaxies. During the last five years, we have conducted detailed numerical studies of the evolution of isolated barred galaxies, focusing on the dynamics, the history of star formation and chemical enrichment, and the effect of AGN feedback. We only considered the secular evolution of galaxies, by ignoring interactions with their surroundings. In the next phase, we will study the impact of external processes such as IGM accretion, external tidal fields, and ram pressure stripping. These processes can greatly affect the evolution of the galaxies, by increasing or depleting the supply of gas available for forming stars and feeding the central AGN, and by destroying or reforming a bar, with major consequences for the dynamics of gas flows in the galaxies. The ultimate goal of this long-term program is to understand the physical principles that determine the history of star formation and chemical enrichment in barred galaxies, explain the correlation (or lack of) between the presence and strength of bars, enhanced star formation and enhanced metallicity, and determine the role played by feedback and external processes in trigerring or quenching star formation in barred galaxies.******The second component consists of studying the chemical enrichment processes of galaxies and their environment. Our objective is to better understand the formation and evolution of galaxies in general by using different observables/tracers, with the goal to converge toward a coherent and consistent picture of galaxies and intergalactic medium (IGM) evolution. For this purpose, we have developed an innovative numerical algorithm that can simulate concurrently the evolution of galaxies and the IGM, and their mutual interactions. In the next phase, we will use this algorithm to reproduce the distribution and properties of galaxies and the structure of the IGM from redshift 6 to the present. We will then produce a database of synthetic absorption spectra of high-redshift quasars, and compare these synthetic spectra with recent observations of DLAs. This will provide statistics for the properties of galaxies (mass, redshift, evolutionary state, environment), as a function of the chemical signatures in the spectra. Using the same database, we will study the various mechanisms responsible for the chemical enrichment of the IGM (galactic winds, ram pressure stripping, tidal disruption, ...). The objective is to determine the relative contribution of these processes, and their dependence on redshift or environment (galaxy clusters vs. field). In a separate project, we will generate synthetic integrated spectra of galaxies, to be compared with observations. The goal is to determine if these observations can be used as a tracer of galaxy evolution.

拟议的研究计划分为两个独立的部分。第一个组成部分是对棒旋星系形成和演化的数值研究。在过去的五年里，我们对孤立的棒状星系的演化进行了详细的数值研究，重点关注动力学、恒星形成和化学富集的历史，以及活动星系核反馈的影响。我们只考虑星系的长期演化，而忽略了与周围环境的相互作用。下一阶段，我们将研究IGM吸积、外部潮汐场和冲压压力剥离等外部过程的影响。这些过程可以极大地影响星系的演化，通过增加或耗尽可用于形成恒星和为中央活动星系核提供能量的气体供应，以及通过破坏或重组棒，对星系中气流的动力学产生重大影响。这个长期计划的最终目标是了解决定棒状星系中恒星形成和化学富集历史的物理原理，解释棒状星系的存在和强度之间的相关性（或缺乏）、增强的恒星形成和增强的恒星形成。金属丰度，并确定反馈和外部过程在棒状星系中触发或熄灭恒星形成中所起的作用。******第二部分包括研究星系及其环境的化学富集过程。我们的目标是通过使用不同的可观测值/示踪剂更好地了解星系的形成和演化，目标是形成连贯一致的星系和星系间介质（IGM）演化图景。为此，我们开发了一种创新的数值算法，可以同时模拟星系和 IGM 的演化以及它们之间的相互作用。下一阶段，我们将使用该算法重现从红移6到现在的星系分布和性质以及IGM的结构。然后，我们将建立一个高红移类星体合成吸收光谱的数据库，并将这些合成光谱与最近对 DLA 的观测进行比较。这将提供星系特性（质量、红移、演化状态、环境）的统计数据，作为光谱中化学特征的函数。使用相同的数据库，我们将研究导致 IGM 化学富集的各种机制（银河风、冲压压力剥离、潮汐破坏……）。目标是确定这些过程的相对贡献，以及它们对红移或环境（星系团与场）的依赖性。在一个单独的项目中，我们将生成星系的合成积分光谱，以与观测结果进行比较。目标是确定这些观测结果是否可以用作星系演化的示踪剂。