Astronomy and Astrophysics

天文学和天体物理学

• 批准号: CRC-2021-00376
• 负责人: Damjanov, Ivana
• 金额: $ 5.46万
• 依托单位: Saint Mary's University
• 依托单位国家: 加拿大
• 项目类别: Canada Research Chairs
• 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=743940
• 关键词: Astronomy; Astrophysics

The most massive galaxies of the early universe are different from their descendants observed in our galactic neighbourhood. When they stop forming stars, these distant "island universes" contain at least as many stars as the Milky Way. However, their stars are packed into volumes thousands of times smaller than the volume of the Milky Way. Theoretical models of galaxy formation and evolution predict that these dense systems should grow through mergers and interactions with other galaxies as the universe matures.Galaxy surveys that cover large volumes and include both dense spectroscopy and high-quality imaging are uniquely suited to map out how today's galaxies assemble their mass. As CRC in Astronomy and Astrophysics Dr. Damjanov uses this synergy to probe the relations between galaxy size growth, the changes in their stellar and (invisible) dark matter content, and their position within the web that the invisible cosmic material weaves throughout the universe. She has discovered that the average rate at which galaxies grow in size after they cease forming stars depends critically on galaxy mass. Combining the observations of galaxies in the nearby and in more distant (and thus earlier) universe, she has demonstrated that massive galaxies indeed grow preferentially through mergers with less massive systems. Proposed research will take current spectroscopic surveys with high-resolution imaging to the next level by including hundreds of thousands of galaxies observed to distances and cosmic times when the universe was half of its current age. Dr. Damjanov will probe how the way galaxies grow changes depending on their location with respect to the cosmic web. She will employ innovative techniques based on artificial intelligence to comb through vast volumes of galaxy images and construct the largest to-date samples of galaxies with signatures of resent mergers in their light profiles. Studying these peculiar galaxies will unveil the types of gravitational interactions that shape them. Massive clusters of galaxies that illuminate knots of the cosmic web harbour large amounts of dark matter. This invisible mass bends the light coming from larger distances, distorting (and even multiplying) galaxy images into arc-like shapes. Dr. Damjanov will study these signatures in galaxy clusters from her survey to trace, in the most direct way possible, simultaneous evolution of luminous and invisible matter throughout the second half of cosmic history.

早期宇宙中最庞大的星系与在我们银河邻里观察到的后代不同。当他们停止形成星星时，这些遥远的“岛屿宇宙”至少包含与银河系一样多的星星。但是，它们的恒星比银河系的体积小数千倍。星系形成和进化的理论模型预测，随着宇宙的成熟，这些密集系统应通过合并以及与其他星系的相互作用来增长。覆盖大量量并包括密集光谱和高质量成像的galaxy调查是独一无二的星系组装质量。随着天文学和天体物理学中的CRC，Damjanov博士利用这种协同作用来探测星系大小的增长，其恒星和（无形的）暗物质含量的变化以及它们在网络中的位置，这使得无形的宇宙物质在整个宇宙中编织。她发现，星系停止形成恒星后，星系大小的平均速率严重取决于星系质量。 结合了附近和更遥远（因此更早）宇宙中星系的观察结果，她已经证明，大型星系确实通过具有较少质量系统的合并而优先增长。拟议的研究将通过在宇宙是其当前年龄的一半时，将目前的光谱调查带到了一个高分辨率成像，将高分辨率成像升至一个新的水平。 Damjanov博士将根据其相对于宇宙网络的位置来探讨星系增长的变化方式。她将采用基于人工智能的创新技术来梳理大量的星系图像，并在光线轮廓中构建具有兴趣合并的签名的最早的星系样本。研究这些特殊的星系将揭示塑造它们的重力相互作用的类型。大量的星系簇照亮了宇宙网络的结。这种无形的质量使来自较大距离的光弯曲，将星系图像变形（甚至倍增）成弧形形状。 Damjanov博士将在她的调查中研究这些签名，从她的调查中，以最直接的方式进行跟踪，同时在宇宙历史的下半年同时演变出发光和无形的物质。