RUI: Interstellar Matter Near the Pleiades: Probing the Cloud-Cluster Interaction with Interstellar Absorption Lines

最近的研究表明，熟悉的昂宿星团周围的星云是该星团与星际云意外相遇的结果。来自红外天文卫星的数据揭示了昂宿星团在周围星际介质中的尾迹，并表明存在弓形激波，星系团附近的加热气体压缩了上游物质。怀特博士的研究有以下目标：追踪观测到的星际气体朝向昂宿星团的运动，特别是在星团-云相互作用区域；探索气体中占主导地位的物理条件，并推断恒星与附近气体之间的空间关系；描述星系团中的星际过程，特别是由尘埃颗粒发出的光电子加热气体的主导过程，以及鲜为人知的CH+分子的形成过程。达到这些目的的手段将是在基特峰国家天文台获得星团和背景星的高分辨率、高灵敏度光谱的星际吸收线分析。该奖项是在本科院校研究计划(RUI)下颁发的。

Recent research has demonstrated that the nebulosity surrounding the familiar Pleiades star cluster results from an accidental encounter between the cluster and an interstellar cloud. Data from the Infrared Astronomical Satellite have revealed the wake of the Pleiades in the ambient interstellar medium, and have indicated the existence of a bow shock where heated gas near the cluster compresses the upstream material. Dr. White's research has the following aims: to trace the motions of the interstellar gas observed toward the Pleiades, particularly in the cluster-cloud interaction region; to explore the physical conditions that prevail in the gas and infer the spatial relationships among the stars and the nearby gas; to characterize interstellar processes in the cluster, particularly the dominant process of gas heating by photoelectrons emitted from dust grains and the poorly understood formation process of the CH+ molecule. The means to these ends will be analysis of interstellar absorption lines in high resolution, high sensitivity spectra of cluster and background stars to be obtained at Kitt Peak National Observatory. This award is made under the Research in Undergraduate Institutions (RUI) program.