A Northern Hemisphere Survey of the Diffuse Interstellar H+

该奖项为北方提供仪器和支持 暗星际H-α（6563）半球巡天 具有高通量的氢气复合线 法布里-珀罗光谱仪。 这些观察结果将为 第一次详细的图片的分布和运动 弥漫的星际介质中温暖的、电离的成分。 在许多方面， 通过光学H-α线将类似于早期的所有- 通过无线电21厘米对中性氢进行的巡天 线 科学回报应该是可观的，因为这 电离气体是一个主要的，但知之甚少的组成部分， 星际介质，质量约为三分之一， 中性氢原子的组成， 星际能量预算的一部分;它似乎也是 银河系下部晕中星际物质的主要状态。 因此，这项调查将对我们的 了解星际物质的组成和结构 介质和内部电离和加热的主要过程 银河系的盘和晕 此外，一项调查显示， 需要一个组件来准确解释天空测量数据 在无线电、微波、红外线、紫外线，甚至 伽马射线波长

This award provides instrumentation and support for a northern hemisphere survey of the faint interstellar H-alpha (6563 Angstroms) hydrogen recombination line with a high throughput Fabry-Perot spectrometer. These observations will provide for the first time a detailed picture of the distribution and kinematics of the warm, ionized component of the diffuse interstellar medium. In many respects this survey of the diffuse ionized hydrogen through the optical H-alpha line will be analogous to earlier all- sky surveys of the neutral hydrogen made through the radio 21 cm line. The scientific return should be substantial, since this ionized gas is a major, but poorly understood component of the interstellar medium, which has a mass approximately one-third that of the neutral atomic hydrogen and accounts for a large fraction of the interstellar power budget; it also appears to be the dominant state of interstellar matter in the lower Galactic halo. This survey therefore will have a significant impact on our understanding of the composition and structure of the interstellar medium and the principal processes of ionization and heating within the Galactic disk and halo. Furthermore, a survey of this component is needed for accurate interpretations of sky survey data obtained at radio, microwave, infrared, ultraviolet, and even gamma-ray wavelengths.