The Birth and Death of Stellar Clusters: Uncloaking the Roles of Stars, Gas, and Physical Environment in Nearby Galaxies

恒星团的诞生和消亡：揭示附近星系中恒星、气体和物理环境的作用

• 批准号: 1517819
• 负责人: Rupali Chandar
• 金额: $ 27.02万
• 依托单位: University of Toledo
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2015
• 资助国家: 美国
• 起止时间: 2015-09-01 至 2019-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1517819&HistoricalAwards=false
• 关键词: Birth; Death; Stellar; Clusters; Uncloaking

A better understanding of the full life cycle of star clusters, from birth to death, is important for many areas of astronomy, including the formation and evolution of galaxies, the initial stellar mass function, the fraction of stars forming in clusters, and for understanding whether the conditions for star formation in the early universe when now-ancient globular clusters were young are the same as they are today. The goal of this program is to shed light on two as-yet poorly understood epochs in the life cycle of a star cluster -- just before they are born and very soon after they form.This program supports the training of a postdoctoral researcher. Results from the research done for this project will be used in age-appropriate, hands-on, activities as part of 'Girls in Science', an all-day outreach event aimed to foster middle-school girls' interest in science. The investigators will study the formation of star clusters, and also their destruction, in nearby galaxies. Star cluster formation is one of the most fundamental processes in galaxies, and occurs over an incredibly diverse range of environments and physical conditions, far broader than those found in the Milky Way alone. Clusters are born in the dense parts of giant clouds of molecular gas, and many are subsequently dispersed by several different physical processes. The goal of this program is to shed light on two as-yet poorly understood epochs in the life cycle of a star cluster -- just before they are born and very soon after they form. Observations with the National Science Foundation's new Atacama Large Millimeter Array enable direct study of clouds in distant galaxies covering a much wider range of physical conditions than our nearest neighbors. The properties of these clouds, particularly their mass functions, when compared with those of young star clusters in the same galaxy, provide important clues to understand the efficiency with which stars and clusters form under different physical conditions. Even as clusters are forming within molecular clouds, the energy and momentum injected by newly born massive stars pushes out left-over interstellar material, which eventually shuts off star formation and leaves many young clusters gravitationally unbound. Physical constraints on this process are poor, but measurements of the ionized gas both inside and outside of very young clusters using observations with the newly commissioned Discovery Channel Telescope (DCT) will distinguish between different predictions.

更好地了解星星团从诞生到死亡的整个生命周期，对天文学的许多领域都很重要，包括星系的形成和演化，初始恒星质量函数，恒星在星团中形成的比例，以及了解早期宇宙中星星形成的条件，当现在古老的球状星团还年轻时，与今天一样。 这个项目的目标是阐明星星团生命周期中两个至今知之甚少的时期--它们诞生之前和形成之后不久。为该项目所做的研究结果将用于适合年龄的实践活动，作为“女孩参与科学”的一部分，这是一项旨在培养中学女孩对科学兴趣的全天外联活动。研究人员将研究附近星系中星星团的形成以及它们的毁灭。 星星团的形成是星系中最基本的过程之一，并且发生在一个令人难以置信的多样化的环境和物理条件下，远远超过银河系中发现的范围。 星系团诞生于巨大的分子气体云的致密部分，许多星系团随后被几个不同的物理过程驱散。 这个项目的目标是揭示星星团生命周期中两个至今知之甚少的时期--在它们诞生之前和形成之后不久。 美国国家科学基金会新的阿塔卡马大型毫米阵列的观测使人们能够直接研究遥远星系中的云，这些星系覆盖的物理条件比我们最近的邻居要广泛得多。 这些云的性质，特别是它们的质量函数，当与同一星系中的年轻星星星团进行比较时，为理解恒星和星团在不同物理条件下形成的效率提供了重要线索。 即使星团在分子云中形成，新诞生的大质量恒星注入的能量和动量也会将剩余的星际物质挤出，最终关闭星星的形成，留下许多年轻的星团，使其不受引力的束缚。 这一过程的物理限制很差，但是使用新委托的发现频道望远镜（DCT）对非常年轻的星系团内外的电离气体进行测量将区分不同的预测。