RUI: HII Region Evolution in Extreme Environments

随着观测技术的改进和亚弧秒射电频率观测的可能性，De PreeHII区域的性质逐渐显露出来。然而，这些存在于最大质量的年轻恒星周围的电离气体体积，至少在它们形成和演化的早期阶段，是银河系中最不了解的物体。HII区域的小表亲称为超紧凑（UC）HII区域，与经典教科书中描述的秒差距尺度，光学薄的HII区域非常不同。 证据很清楚：UC HII区域不仅仅是小的HII区域，它们代表了一类独特的物体。Christopher De Pree博士的研究项目的目标是将最近和拟议的观测结果与流体动力学模拟进行比较，以更全面地了解UC HII区域的性质，以及它们的形态，温度，运动学和演化告诉我们大质量星星形成的最早阶段。UC HII区域从未在这些小空间尺度上成像和光谱映射。待研究的源是光学不可观测的，这些将是最好的数据，直到阿塔卡马大型毫米波阵列（阿尔马）在未来十年专用。这些新的数据提供了最好的比较数据，以约束UC HII区域演化的流体动力学模拟。艾格尼丝·斯科特学院方案在使女本科生参与天文学研究并为她们从事研究生工作做好准备方面取得了成功，该项目将继续并加强这一努力，让两个一流的国家研究生方案（北卡罗来纳州州立大学和哈佛大学）的科学家参与研究并接触研究。已与一些调查人员非正式地分享了有关项目的早期数据，该项目将免费提供现有数据和新数据。 该奖项是在NSF的本科院校研究（RUI）计划的赞助下颁发的。

AST-0206103De PreeHII regions have revealed their nature slowly as observational techniques have improved and as subarcsecond radio frequency observations have become possible. Yet, these volumes of ionized gas that exist around the most massive young stars, at least in the early stages of their formation and evolution, are some of the least understood objects in the Galaxy. The diminutive cousins of HII regions called ultracompact (UC) HII regions are very different from the parsec-scale, optically-thin HII regions described in classic textbooks. The evidence is clear: UC HII regions are not simply small HII regions, they represent a unique class of object. The goal of Dr. Christopher De Pree's research project is to compare recent and proposed observations with hydrodynamic simulations to move toward a more complete understanding of the nature of UC HII regions and what their morphologies, temperatures, kinematics and evolution tell us about the earliest stages of massive star formation. UC HII regions have never been imaged and mapped spectroscopically on these small spatial scales. The sources to be studied are optically unobservable, and these will be the best data available until the Atacama Large Millimeter Array (ALMA) is dedicated in the coming decade. These new data provide the best comparison data to constrain hydrodynamic simulations of UC HII region evolution. The Agnes Scott College program has a proven record of success in involving undergraduate women in astronomical research and preparing them for graduate work, and this project would continue and strengthen that effort by providing research involvement and exposure to scientists at two premiere national graduate programs (North Carolina State University and Harvard University). Early data from related projects have been shared informally with a number of investigators, and this project would make existing data and new data freely available. This award is made under the auspices of the Research in Undergraduate Institutions (RUI) program at NSF.***