Science Support for the SCUBA-2 and Herschel Galactic Plane Surveys: Triggered Star Formation in the Galaxy

对星际介质中星星的形成是如何触发或诱导的定量理解是整个天体物理学的基础，但目前还没有。正是这种星星形成的模式导致了早期宇宙中观测到的强烈的恒星爆发。为了实现这一理解，我们需要测量恒星从银河系分子气体云形成的效率，以及形成的新恒星的质量分布，如何随着影响云的物理力的强度而变化，例如风和与热恒星相关的电离区域的扩大，以及超新星爆炸。我们还需要了解星星形成的初始条件：云本身的起源，它们特有的湍流，以及这些条件的差异如何影响自发的星星形成。我们在这方面取得了重大进展，对单个银河系的恒星形成内容进行了全面的观测研究，恒星形成，巨大的分子云。现在的进展需要具有不同初始和环境条件的类似区域的大样本。申请人正在领导一个国际项目，在夏威夷的詹姆斯·克拉克麦克斯韦望远镜上使用由STFC资助的最先进的新仪器对银河平面进行观测。这项调查将产生一个普查的所有高质量星星形成的大部分银河系，这将导致显着的进展领域。它将首次允许研究具有各种内部和外部物理环境的恒星形成区域的代表性样本。申请人还是一个国际财团的主要活跃成员，该财团已在赫歇尔远红外空间观测站获得了300多小时的观测时间，以调查内银河平面。该项目将提供关于星系内部区域SCUBA-2探测到的所有最冷源的光度和温度（因此是进化状况）的重要数据。该研究将揭示初始条件、外部环境和反馈对恒星形成效率和结构质量函数的定量影响。这些结果将促进我们对星星形成的理解，并为其他领域提供有价值的投入，例如星系的形成和演化的研究。

A quantitative understanding of how star formation is triggered or induced in the interstellar medium is fundamental to the whole of Astrophysics but is not yet available. It is this mode of star formation which is responsible for the intense starbursts observed in the early Universe. In order to achieve this understanding, we need to measure how the efficiency with which stars are formed from Galactic molecular gas clouds, and the distribution of the masses of the new stars that form, change with the strength of the physical forces which impact on the clouds, such as the winds and expanding ionised regions associated with hot stars, and supernova explosions. We also need to understand the initial conditions of star formation: the origin of the clouds themselves, their characteristic turbulence and how spontaneous star formation is affected by differences in these conditions. We have made significant progress in this direction with comprehensive observational studies of the star-formation content of single Galactic, star-forming, giant molecular clouds. Progress now requires large samples of similar regions with different initial and environmental conditions. The applicant is leading an international project to survey the Plane of the Galaxy using new, STFC-funded, state-of-the art instrumentation at the James Clerk Maxwell Telescope in Hawaii. This survey will produce a census of all high-mass star formation in a large fraction of the Galaxy which will lead to significant advances in the field. It will allow, for the first time, the study of representative samples of star-forming regions with a variety of internal and external physical environments. The applicant is also a key active member of an international consortium that has secured 300+ hours of observing time on the Herschel far-infrared space observatory, in order to survey the inner Galactic Plane. This project will provide important data on luminosities and temperatures (hence evolutionary status) for all but the coldest sources detected with SCUBA-2 in the inner Galaxy region. The proposed research will reveal the quantitative effect of initial conditions, external environment, and feedback on the star-formation efficiency and structure mass function. The results will create advances in our understanding of star formation and provide valuable input into other fields, such as the study of formation and evolution of galaxies.