Examination of Characteristics of Atmosphere Fluctuations of Importance to Ground-Based Astronomy

对地面天文学重要的大气波动特征的检验

• 批准号: 9119317
• 负责人: Charles Townes
• 金额: $ 29.79万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1992
• 资助国家: 美国
• 起止时间: 1992-04-15 至 1994-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9119317&HistoricalAwards=false
• 关键词: Examination; Characteristics; Atmosphere; Fluctuations; Importance

This award supports measurement and analysis of the nature of fluctuations in optical paths through the atmosphere. The results should be of importance for optimizing designs for adaptive optics, for large telescopes, and for spatial interferometers operating from the ground. Measurements will be made with the Infrared Spatial Interferometer (ISI) now installed on Mount Wilson, which has already been useful in initiating such measurements. The initial measurements appear to show that for conditions encountered in ground-based astronomy, pathlength fluctuation often differ significantly from those expected on the basis of the standard model of Kolmogorov turbulence and Taylor's approximation. Furthermore, these deviations can have a significant bearing on the design of future large aperture instruments and their extension into the infrared region. The program will measure fluctuations in pathlength differences from a stellar object to the two telescopes and also fluctuations near the ground at the position of the two telescopes. These will be correlated with such parameters as wind speed, time of day, astronomical seeing, and cloud cover. The measurements will yield the structure function of time, Allan variances, and power spectra. In addition, examination of correlations between the laser interferometers and the IR interference fringe signals with various telescope separations will provide direct information on the structure function of distance. Observations over a period of time and under various conditions applicable to astronomical observations from the ground are needed in order to obtain an adequate statistical sample.

该奖项支持测量和分析的性质， 大气中的光路波动。 结果 对于优化自适应光学的设计应该是重要的， 对于大型望远镜和空间干涉仪来说， 从地上 测量将使用红外 空间干涉仪（ISI）现在安装在威尔逊山， 已经在启动这种测量中发挥了作用。 的 初步测量似乎表明，对于遇到的条件， 在地基天文学中，光程起伏常常不同， 与标准预期值相比， Kolmogorov湍流模型和Taylor近似。 此外，这些偏差可能对以下方面产生重大影响： 未来大口径仪器的设计及其推广 进入红外区域。 该程序将测量波动 从恒星物体到两个恒星物体的路径长度差异 望远镜和地面附近的波动 这两个望远镜。 这些将与这样的 风速，一天中的时间，天文视宁度， 云层覆盖。 测量将产生结构函数 时间、Allan方差和功率谱。 此外，本发明还提供了一种方法， 检查激光干涉仪和 不同望远镜红外干涉条纹信号 分离将提供关于结构的直接信息 距离的函数。 在一段时间内和 适用于天文观测的各种条件 为了获得足够的统计数据， sample.