Supernova Remnants, Superbubbles, and Feedback in Disk Galaxies

对附近一些星系中热气的X射线观测揭示了X射线超泡和新近恒星形成地点之间的紧密空间关联。威斯康星大学麦迪逊分校的Eric Wilcots博士将对这些星系进行灵敏的射电连续观测，以探测大量射电超新星遗迹(SNR)，并将它们的能量和空间分布与观测到的X射线超泡联系起来。结果将是对超泡追踪最近超新星爆炸分布这一命题的直接检验，以及对宇宙射线能量追踪超泡热能的程度的衡量。这组新的射电连续谱观测还将产生迄今为止最灵敏的信噪比搜索结果，并将为每个星系提供定义良好的信噪比光度函数和光谱指数分布。这一科学计划是一项广泛的努力，旨在了解SNR、超泡和盘状星系中星际介质的整体演化之间的关系。该计划的结果将显示信噪比和X射线超气泡在空间和能量上的关联程度，并准确地描绘具有一定恒星形成率范围的盘状星系样本的信噪比光度函数。除了研究目标外，该计划还将在整个过程中支持一名全日制研究生和大约6至10名本科生的培训。该计划还将为与威斯康星大学太空广场相关的扩展活动提供关键支持，该中心是天文系的校外扩展中心。

X-ray observations of hot gas in a number of nearby galaxies have revealed a tight spatial correlation between X-ray superbubbles and sites of recent star formation. Dr. Eric Wilcots (University of Wisconsin-Madison) will obtain sensitive radio continuum observations of these same galaxies in order to detect large numbers of radio supernova remnants (SNRs) and correlate their energies and spatial distribution with the observed X-ray superbubbles. The result will be a straightforward test of the proposition that superbubbles trace the distribution of recent supernova explosions, as well as a measure of the extent to which the cosmic ray energy traces the thermal energy of the superbubble. The new set of radio continuum observations will also result in the most sensitive searches for SNRs to date and will yield a well defined SNR luminosity function and spectral index distribution for each galaxy. This scientific program is a broad effort to understand the relationships between SNRs, superbubbles, and the overall evolution of the interstellar medium in disk galaxies. The results of this program will show the extent to which SNRs and X-ray superbubbles are spatially and energetically correlated, and accurately depict the SNR luminosity function for a sample of disk galaxies with a range of star formation rates.In addition to the research goals, this program will support the training of one full time graduate student and some 6 to 10 undergraduates over the course of its duration. This program will also provide key support of the outreach activities associated with University of Wisconsin Space Place, the off-campus outreach center of the Department of Astronomy.