Astrophysical and Astrochemical Tests of Massive Star Formation Theories

质量比太阳大得多的恒星是推动银河系演化的引擎；星际气体和尘埃与它们的风、辐射混合在一起，最终在超新星爆炸中猛烈死亡。这个项目将提高我们对这些质量最大的恒星是如何形成的理解。该项目将开发新的理论和计算模型，模拟这些大质量恒星的形成过程，从它们作为星际氢气的凝聚核开始，到它们作为我们银河系中最大的恒星诞生。这些新的模拟将包括更真实的原恒星核心演化模型、旋转流入物质的周围区域以及新形成的恒星的外流风。该项目将利用最先进的设备在毫米、亚毫米和中红外波长进行新的观测，以测试和验证这些大质量恒星形成的模型。该项目将使用现有的蒙特卡罗辐射传输程序来处理湍流吸积岩芯，PI已对其进行了修改，以包括尘埃和气体不透明度。这些模型将被用来扩展大质量恒星的正则演化序列，以系统地涵盖更大的初始核心质量、核心自转和环境因素的参数空间。提出者还将把尘埃颗粒排列和双星效应的新模型纳入到目前的辐射传输计算中。辐射传递计算的输出将包括可与阿塔卡马大毫米/亚毫米阵列(ALMA)等设施的观测相比较的可观测数据。该项目将建立在国际和平研究所以前为培训新一代科学家所做的努力的基础上，重点是来自代表性不足群体的学生。该项目将通过制作题为？巨人队的诞生？的演示文稿向公众公布其结果。宇宙中最大质量的恒星？将在当地学校和佛罗里达自然历史博物馆组织的活动中展出。

Stars with masses much greater than that of our Sun are the engines that drive the evolution of our galaxy; mixing the interstellar gas and dust with their winds, radiation, and eventually their violent deaths in supernova explosions. This project will improve our understanding of the way in which the most massive of these stars are formed. The project will develop new theoretical and computational models that simulate the formation of these massive stars from their beginnings as condensing core of interstellar hydrogen gas to their birth as the largest stars in our galaxy. These new simulations will include more physically realistic models of the evolution of the proto-stellar core, the surrounding region of rotating infalling matter, and the outflowing winds from the newly forming star. The project will test and verify these models of massive star formation with new observations with state-of-the-art facilities performed at millimeter, sub-millimeter, and mid-infrared wavelengths. The project will use existing Monte Carlo radiative transfer code for turbulent accreting cores, which the PI has modified to include both dust and gas opacities. These models will be used to extend the canonical evolutionary sequence for massive stars to systematically cover a much larger parameter space of initial core mass, core rotation, and environmental factors. The proposers will also incorporate new models for dust grain alignment and the effects of a binary companion to the current radiative transfer computations. The output of the radiative transfer calculations will consist of observables that can be compared with observations by facilities such as the Atacama Large Millimeter/Sub-millimeter Array (ALMA).This project will build upon previous efforts by the PI to train of a new generation of scientists, with a strong emphasis on students from underrepresented groups. The project will communicate its results to the public through the development of a presentation entitled ?Birth of the Giants ? the Most Massive Stars in the Universe? to be shown at local schools and at events organized through the Florida Museum of Natural History.