Asteroseismology of Sun-like Stars

梅特卡夫博士获得了美国国家科学基金会天文学和天体物理学博士后奖学金，在科罗拉多州博尔德的国家大气研究中心高海拔天文台开展研究和教育项目。星震学通过将观测到的振荡频率与恒星模型相匹配，为探测脉动恒星的内部结构提供了一个独特的机会。目前和计划中的几个卫星任务将很快对几十颗类太阳恒星进行革命性的观测。从这些数据中得出可靠的地震学约束将需要我们在分析方法上进行重大改进。梅特卡夫博士将开发一种复杂的计算方法，用于对类太阳恒星进行全球地震学分析。该项目的三个阶段将包括：1)采用一种基于遗传算法的优化技术，该技术最初是为脉动白矮星模型开发的，用于与主序模型接口；2)将该技术应用于目前最有希望用于星震学的主序候选者Delta-Scuti恒星的现有观测；3)利用合成数据和天基观测资料记录该方法在类太阳振荡上的表现。梅特卡夫项目的一个重要部分是通过互联网将他的日常研究与外展活动结合起来，使他能够以一种广泛可访问的形式传播结果。他将参与“宇宙之窗”项目的内容开发，这是一个面向公众的基于网络的学习系统。这个资源可以方便地访问多个教育层次的地球和空间科学信息的众多来源。梅特卡夫将主要在与白矮星和脉动恒星有关的领域做出贡献。

Dr. Metcalfe is awarded an NSF Astronomy and Astrophysics Postdoctoral Fellowship to carry out a program of research and education at the High Altitude Observatory of the National Center for Atmospheric Research in Boulder, Colorado. Asteroseismology provides a unique opportunity to probe the internal structure of pulsating stars, by matching the observed oscillation frequencies with stellar models. Several current and planned satellite missions will soon yield observations of revolutionary quality for dozens of Sun-like stars. Deriving reliable seismological constraints from these data will require a significant improvement in our analysis methods. Dr. Metcalfe will develop a sophisticated computational method for global seismological analyses of Sun-like stars. The three phases of the project will involve 1) adapting an optimization technique based on a genetic algorithm, originally developed for models of pulsating white dwarfs, to interface with main-sequence models, 2) applying this technique to existing observations of Delta-Scuti stars, currently the most promising main-sequence candidates for asteroseismology, and 3) documenting the performance of the method on solar-like oscillations using both synthetic data and space-based observations when they become available.An important part of Metcalfe's project is to integrate his daily research with outreach activities through the Internet, allowing him to disseminate the results in a form that is broadly accessible. He will participate in content development for the "Windows to the Universe" project, a web-based learning system for the general public. This resource allows easy access to numerous sources of Earth and Space Science information at multiple educational levels. Metcalfe will contribute primarily in areas related to white dwarfs and pulsating stars.