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: 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=763024
• 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（称为致密核心）中，而致密核心通常在较大的星团或星团中形成，尽管包括太阳在内的大多数恒星都是以星团形式形成的，但我们对这种形成模式知之甚少。与孤立形成的恒星相比，了解恒星如何在星团中形成会影响各种科学问题，包括使用阿塔卡马这样的新望远镜是否能够形成。大毫米阵列 (ALMA) 和詹姆斯·韦伯太空望远镜 (JWST) 上线并提供有关恒星形成星团的壮观新视图，现在正是在该领域进行详细研究的最佳时机。我的研究计划的重点是测量星团的初始条件。星团的形成以及星团成员如何形成和获得质量的过程中，我正在开发一个新的星团目录，这些星团在恒星开始诞生之前就被捕获，这些星团的致密核心是使用詹姆斯·克拉克·麦克斯韦望远镜的古尔德来识别的。带调查是这项工作的首要调查，这个对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，该调查提供了对大片天空中稠密气体运动的首批详细测量结果之一，结合 GAS 和 GBS 数据将使我的团队能够充分描述特征。属性该提案的第二个方面是测试一种流行的簇形成模型；丝状结构负责提供形成簇成员所需的大部分材料，该模型的系统验证将是可能的。结合 GBS 和 GAS 数据集以及一些额外的观察结果，我的建议的第三个方面将通过深入研究前两个方面来增强。星团形成系统子集的精细尺度细节将使用扬斯基甚大阵列和 ALMA 进行测量，这些观测结果将揭示反映星团难以测量特性的结构特征。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以及核心如何通过这三个方面的综合结果获得质量。小密的核心星团将被更好地理解，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星团中形成的。