On the Formation and Destruction of Giant Molecular Clouds in Galaxies

如果我们要了解太阳和地球是如何形成的，我们必须首先了解银河系本身是如何形成的，以及它如何随着时间的推移而变化。 天文学家知道银河系包含巨大的气体和尘埃云。 正是从这些“巨分子云”（GMC）中诞生了所有的恒星。 这个项目的目标是了解这些巨大的云是如何形成的，以及它们在数百万年间是如何变化的。 获奖者将利用多年来开发的计算机模型，研究超大型恒星的爆炸如何影响云层。 这些模型包括许多已知会影响银河系中气体的因素：气体的温度和密度，银河系的旋转，银河系中数十亿颗恒星发出的光，甚至是云中原子和分子的化学性质。 大部分工作将由博士后研究员完成，由首席研究员（PI）指导，他是世界知名的银河系天文学和恒星诞生专家。 研究生和本科生也将参与这项研究，女高中生将被邀请到PI的研究所，以跟踪毕业生和早期职业科学家。 PI希望通过这种方式激励新一代年轻的女性研究人员。该项目旨在继续在非常大的空间尺度（GMC及以上）上对星星形成进行数值模拟。 新的模型将包括电离和非电离紫外线辐射，超新星反馈，湍流，磁场，化学和星系切变。 这些影响中有许多被排除在过去的模型之外，或者单独使用，而不是组合使用。 该项目将使用先进的计算方法来模拟GMC的形成和破坏，提供第一个完全自洽的高分辨率磁流体动力学（MHD）和辐射MHD模型，并进行物理和化学的综合处理。 这样的建模是有用的，不仅在合成银河系中的星星形成和GMC演化，但也可能被用来解释新的阿尔马观测其他附近的星系。

If we are to understand how the Sun and Earth formed, we must first understand how the Galaxy itself was formed and how it changes over time. Astronomers know that the Milky Way Galaxy contains huge clouds of gas and dust. It is from these "Giant Molecular Clouds" (GMCs) that all stars are born. The goal of this project is to understand how these giant clouds are formed and how they change over millions of years. Using computer models developed over a number of years, the awardee will investigate how the explosions of very large stars affect the clouds. The models include many of the things known to affect the gas in the Milky Way: the temperature and density of the gas, the rotation of the Milky Way, the light from the billions of stars in the galaxy, and even the chemistry of the atoms and molecules in the clouds. Much of the work will be done by a postdoctoral researcher, guided by the Principal Investigator (PI) who is a world-renown expert in Milky Way astronomy and the birth of stars. Graduate and undergraduate students will also be involved in the research, and female high-school students will be invited to the PI's institute to shadow graduates and early-career scientists. In this way the PI hopes to inspire a new generation of young, female researchers.The project seeks to continue numerical modeling of star formation on very large spatial scales (GMCs and above). The new models will include ionizing and non-ionizing UV radiation, supernova feedback, turbulence, magnetic fields, chemistry, and galactic shear. Many of these effects have been excluded from past models or used individually rather than in combination. This project will use advanced computational methods to simulate GMC formation and destruction, providing the first fully self-consistent magnetohydrodynamic (MHD) and radiation MHD models at high resolution and with comprehensive treatment of physics and chemistry. Such modeling is useful not only in synthesizing star formation and GMC evolution in the Milky Way Galaxy but may also be used to interpret new ALMA observations of other, nearby galaxies.