Investigating the Formation of Small Protostellar Clusters

研究小型原恒星团的形成

• 批准号: RGPIN-2019-04403
• 负责人: Kirk, Helen
• 金额: $ 1.75万
• 依托单位: University of Victoria
• 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=679815
• 关键词: Investigating; Formation; Small; Protostellar; Clusters

Stars are born within cold, dense condensations of gas and dust, known as dense cores, which in turn usually form within larger associations or clusters. Despite most stars, including our Sun, having formed in clusters, we know much less about this formation mode than stars forming in isolation, due to the more challenging nature of the observations required. Understanding how stars form in clusters impacts a variety of science questions, including whether solar systems like our own would be able to form. With new telescopes such as the Atacama Large Millimetre Array (ALMA) and the James Webb Space Telescope (JWST) coming online and offering spectacular new views on star-forming clusters, the time is right to pursue a detailed study in this area. ******My research program centres on measuring the initial conditions for cluster formation and how cluster members form and gain mass. In preparation for my NSERC grant, I am developing a novel catalogue of clusters caught before they begin birthing stars. These clusters of dense cores are identified using the James Clerk Maxwell Telescope's Gould Belt Survey, the premier survey for this work. This unique sample of very young and nearby clusters forms the launching point of my group's broader investigation into cluster formation.******The first prong of my proposal is to characterize the motions of the gas associated with forming clusters. Observations will be provided by the recently completed Green Bank Ammonia Survey (GAS), which is providing one of the first detailed measurements of dense gas motion across large areas of the sky. Combining the GAS and GBS data will allow my group to fully characterize the properties of these young cluster-forming systems.******The second prong of the proposal is to test a popular model of cluster formation wherein filamentary structures are responsible for supplying most of the material needed to form the cluster members. Systematic verification of this model will be possible, using a combination of the GBS and GAS datasets, along with some additional observations. This analysis will be the first of its kind around such young and small clusters.******The third prong of my proposal augments the first two prongs by delving into the cluster-forming regions at higher angular resolution. The fine scale details of a subset of the cluster forming systems will be measured using the Jansky Very Large Array and ALMA. These observations will reveal features in the structures that reflect difficult to measure properties of the cluster environment. For example, the level of substructure within a dense core (smooth versus multi-peaked) reflects how much turbulent motion is present and how the core is able to gain mass.******Through the combined results of these three prongs, the formation and evolution of small dense core clusters will be better understood. The results will additionally guide future analyses of larger and more complex clustered systems, within which the majority of stars formed.**

恒星诞生于寒冷、致密的气体和尘埃凝结物中，称为致密核心，而致密核心通常是在更大的联合体或星团中形成的。尽管包括太阳在内的大多数恒星都是以星团形式形成的，但由于所需的观测更具挑战性，我们对这种形成模式的了解远少于孤立形成的恒星。了解恒星如何在星团中形成会影响各种科学问题，包括是否能够形成像我们这样的太阳系。随着阿塔卡马大型毫米波阵列 (ALMA) 和詹姆斯·韦伯太空望远镜 (JWST) 等新型望远镜的上线并提供有关恒星形成星团的壮观新视野，现在正是在这一领域进行详细研究的最佳时机。 ******我的研究项目集中在测量星团形成的初始条件以及星团成员如何形成和增加质量。为了准备我的 NSERC 拨款，我正在开发一个新颖的星团目录，其中包含在恒星诞生之前捕获的星团。这些致密核心簇是使用詹姆斯·克拉克·麦克斯韦望远镜的古尔德带巡天来识别的，这是这项工作的首要巡天。这个非常年轻和附近星团的独特样本构成了我的小组对星团形成进行更广泛研究的起点。******我的建议的第一个方面是描述与形成星团相关的气体运动的特征。最近完成的绿岸氨调查（GAS）将提供观测结果，该调查是对大片天空中稠密气体运动的首批详细测量之一。结合 GAS 和 GBS 数据将使我的团队能够充分表征这些年轻的团簇形成系统的特性。********该提案的第二个方面是测试一种流行的团簇形成模型，其中丝状结构负责提供形成集群成员所需的大部分材料。 结合使用 GBS 和 GAS 数据集以及一些额外的观察结果，可以对该模型进行系统验证。这项分析将是围绕此类年轻和小型星团进行的首次分析。******我提案的第三个方面通过深入研究更高角分辨率的星团形成区域来增强前两个方面。星团形成系统子集的精细尺度细节将使用 Jansky 甚大阵列和 ALMA 进行测量。这些观察结果将揭示结构中的特征，这些特征反映了难以测量的集群环境的特性。例如，致密核心内的子结构水平（平滑与多峰）反映了存在多少湍流运动以及核心如何能够获得质量。******通过这三个方面的综合结果，小型致密核心团簇的形成和演化将得到更好的理解。这些结果还将指导未来对更大、更复杂的星团系统的分析，大多数恒星是在这些系统中形成的。**