Clustered Star Formation on various scales. An extensive panchromatic stellar survey of star-forming galaxies in the Local Group with the Hubble Space Telescope

恒星是以不同的尺度和不同程度的引力自束缚形成的。从小的致密星团到大的松散复合体，各种各样的恒星聚集在一个星系中，承载着星系中的大多数年轻恒星，并为其场提供恒星，在星系演化中发挥着基础性的作用。这个DFG项目将利用哈勃太空望远镜(HST)进行的三次独特的银河系外深部恒星调查，以解决关于不同尺度和环境的恒星结构形成和演化的基本问题。该项目的第一个资助期支持我对全色哈勃太空望远镜仙女座星系国库计划(PI：J.J.Dalcanton)的贡献，该计划是仙女座星系迄今实现的最完整的恒星覆盖。尽管调查尚未完成，但调查部分的第一批数据提供了关于星系规模的星团恒星形成的显著结果。应用的扩展将允许该项目通过充分利用完整的调查来参与对仙女座星系的全球天体物理推断。它还将使我们能够通过利用另外两个HST金库计划的数据，在各种环境和广泛的时间和空间尺度上进一步研究星团的恒星形成：(I)蜘蛛星云令人印象深刻的恒星形成区域，将利用哈勃蜘蛛星云国库计划(PI：E.Sabbi)的数据进行研究；以及(Ii)传统的河外紫外线探测(PI：D.Calzetti)将在五个波段建立最完整的恒星调查，该探测包括本地组的50个恒星形成螺旋和矮星系。这些计划将通过将仙女座菌株的发现扩展到一系列特殊的恒星形成环境来促进DFG项目的科学影响。这一雄心勃勃的项目将与全球40多名同事合作，理解恒星成组形成的重要问题。该项目的直接目标是了解：(1)星团恒星形成在时间和空间上是如何进行的；(2)形成时是什么机制决定了恒星结构；(3)观测到的星团星团在大小、形状和致密性方面的变化源于什么；(4)环境如何影响星团恒星形成及其随后的动态演变。对河外恒星群进行的所有三次深全色HST观测的数据将大大推动对这些主题的广泛空间分辨率的研究，从大麦哲伦星云的微秒级到仙女座星系的10微秒级，再到更远的星系的100微秒级。在一大批星系中分解的各种恒星群将提供前所未有的样本，以彻底和一致的方式研究恒星结构的形成和演化。

Stars are formed in groups of various scales and with various degrees of gravitational self-binding. A large variety of stellar concentrations, from small compact clusters to large loose complexes, host the majority of young stars in a galaxy, and feed its field with stars, playing a fundamental role in galaxy evolution. This DFG project will utilize three unique deep extragalactic stellar surveys with the Hubble Space Telescope (HST) to address fundamental questions on the formation and the evolution of structures of stars on various scales and environments.The first funding period of the project supported my contribution to the Panchromatic Hubble Space Telescope Andromeda Galaxy Treasury program (PI: J. J. Dalcanton), on the most complete stellar coverage ever achieved in the Andromeda galaxy. Although the survey is not yet complete, first data on portions of the survey delivered remarkable results on clustered star formation at galactic scales. The applied extension will allow the participation of this project to the global astrophysical inference of the Andromeda galaxy through the full exploitation of the complete survey. It will also allow us to further investigate clustered star formation in a variety of environments, and across a wide range of time and spatial scales, through the employment of data from two additional HST Treasury programs: (i) The impressive star-forming region of the Tarantula Nebula, will be investigated with data from the Hubble Tarantula Nebula Treasury Program (PI: E. Sabbi), and (ii) the Legacy ExtraGalactic UV Survey (PI: D. Calzetti) will construct the most complete stellar survey in five wavebands of 50 star-forming spiral and dwarf galaxies in the Local Group. These programs will advance the scientific impact of this DFG project, by extending the Andromeda findings to an exceptional collection of star-forming environments.This ambitious project will comprehend important issues of the formation of stars in groups in collaboration with more than 40 colleagues worldwide. Direct objectives of the project is to understand: (1) How clustered star formation proceeds in time and space; (2) Which mechanisms determine stellar structure at the time of formation; (3) What is the origin of the observed variety in size, shape and compactness in stellar clusterings; (4) How the environment affects clustered star formation and its subsequent dynamical evolution. Data from all three deep panchromatic HST surveys of extragalactic stellar populations will significantly advance the investigation of these topics in a wide range of spatial resolutions, starting from parsec-scale in the Large Magellanic Cloud, to 10 parsec-scale in the Andromeda galaxy, to 100 parsec-scale, in more distant galaxies. The various stellar populations, resolved in a large collection of galaxies, will provide unprecedented samples to address stellar structure formation and evolution in a thorough and consistent way.