Resolving the Role of Neutral Gas in Galaxy Evolution

解决中性气体在星系演化中的作用

• 批准号: RGPIN-2022-03499
• 负责人: Rosolowsky, Erik
• 金额: $ 3.64万
• 依托单位: University of Alberta
• 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=762569
• 关键词: Resolving; Role; Neutral; Gas; Galaxy

One of the major goals for Canadian astrophysics over the next decade is to understand the origins of galaxies. Unravelling this mystery is a vital step in understanding the scientific story of our origins, explaining the conditions where the Sun formed but also all the stars around us. We understand broadly that stars form out of cold clouds of molecular gas, and we also understand that short-lived stars so formed will evolve and die relatively quickly, returning their material to be incorporated into the next generation of stars. This baryon cycle can explain how the heavy elements that make up our planet and our bodies came from a previous generation of stars. However, the actual physics that drives the baryon cycle is poorly understood. To understand this essential cycle, this research will use a suite of new telescope observations to make the best available census of these internal processes that control galaxy evolution. Specifically, this research will measure how the process of star formation changes in response to the local environments within galaxies, answering questions like: how quickly does star formation take place in molecular gas? What physical effects control that rate? What physical processes affect the efficiency of turning its gas into stars? How do dying stars stir up or destroy their local environments? What causes a cloud of gas to cool and start forming stars? We can now address these questions by making high resolution observations of nearby galaxies using some of the best telescopes on Earth and in space. The essential feature across all our new observations is that they must be able to measure the small details of star formation (high-resolution). We have collected new data sets with the Atacama Large Millimeter/submillimeter array to map out the properties of star forming clouds of gas and the Hubble Space Telescope and the Very Large Telescope to study the properties of the recently formed stars. Our group will use these data to measure the efficiency of star formation. We will also collect new data using the James Webb Space Telescope, which should launch at the end of 2021, to see the stars that are right in the middle of formation, which will provide new insights on how quickly star formation proceeds. Finally, we are using the Very Large Array to study the warm gas, which acts as an intermediary: receiving material from dying stars and cooling down to form the next generation of star-forming clouds. These observations will measure how dying stars disrupt their local environment as well as giving new insights into how gas clouds start forming stars. These are central questions to understanding galaxy evolution, but our progress has been limited because we could only make detailed studies of star formation in our own Milky Way galaxy. By observing other galaxies, we can finally see star formation from the "top down," which allows us to see how star formation connects back to the broader galaxy.

在未来十年中，加拿大天体物理学的主要目标之一是了解星系的起源。揭开这个谜团是理解我们起源科学故事的至关重要的一步，解释了太阳形成的条件以及我们周围的所有星星。 我们广泛地理解，恒星是由分子气的冷云形成的，我们也知道，如此形成的短寿命会相对迅速地发展和死亡，从而将其材料返回以掺入下一代恒星中。这个重子周期可以解释构成我们星球和身体的重型元素如何来自上一代恒星。但是，驱动重子循环的实际物理学知之甚少。 为了理解这一基本周期，这项研究将使用一套新的望远镜观测值，以对控制星系演变的这些内部过程进行最佳的普查。具体而言，这项研究将衡量恒星形成的过程如何响应星系中的本地环境，回答以下问题：恒星形成在分子气中发生的速度？哪些物理效应控制该速率？哪些物理过程会影响将其气体变成恒星的效率？垂死的星星如何搅动或破坏其当地环境？是什么导致气体冷却并开始形成恒星？现在，我们可以使用地球和太空中一些最好的望远镜对附近星系进行高分辨率观察来解决这些问题。我们所有新观察的基本特征是，它们必须能够测量恒星形成的小细节（高分辨率）。我们已经使用Atacama大毫米/亚毫米阵列收集了新的数据集，以绘制出恒星形成气体云和哈勃太空望远镜的特性，以及非常大的望远镜，以研究最近形成的恒星的性质。我们的小组将使用这些数据来衡量恒星形成的效率。我们还将使用詹姆斯·韦伯（James Webb）太空望远镜（James Webb Space Telescope）收集新数据，该望远镜应在2021年底启动，以查看正好在编队中间的星星，这将提供有关恒星编队的速度进行的新见解。最后，我们正在使用非常大的阵列来研究温暖的气体，该阵列充当中介：从垂死的恒星中接收材料并冷却以形成下一代恒星形成云。这些观察结果将衡量垂死的星星如何破坏其当地环境，并为气体云开始形成恒星的新见解。这些是理解星系进化的核心问题，但是我们的进步受到限制，因为我们只能以自己的银河系为星系进行详细研究恒星形成。通过观察其他星系，我们最终可以从“自上向下”看到恒星形成，这使我们能够看到恒星形成如何连接到更宽的星系。