Absolute Cross Section Measurements for the Production of NIand NII Fluorescense through Photoexcitation on N 2

该基金支持测量N2光解激发产生NI 120nm发射的荧光截面，从各自的阈值到200A。这样的横截面是精确定量分析和评估地球氮日光模型所必需的。NI 120纳米测量的拟议工作将使用现有的仪器进行，这些仪器已由本小组开发，用于南加州大学的光源和威斯康星大学同步辐射设施的同步辐射源。NII测量需要一个光谱带宽为10A的小型Seya-Namioka型单色仪。希望这也将有可能测量产生(1)N2的NI 113.4, 142.1, 149.3和174.3nm发射和(2)O2的OI 130.4和OI 135.6nm和OII 102.5nm的截面函数。

This grant supports work to measure the fluorescence cross sections for producing the NI 120nm emission from photodissociative excitation of N2 from their respective thresholds to 200A. Such cross sections are required for accurate quantitative analysis and for assessments of models of the Earth's nitrogen dayglow. The proposed work on the NI 120nm measurements will be carried out with existing instrumentation which has been developed by the present group for use with light sources at USC and the synchrotron radiation source at the University of Wisconsin Synchrotron Radiation Facilities. A small Seya-Namioka type monochromator with a spectral bandwidth of 10A is required for the NII measurements. It is hoped that it will also be possible to measure the cross section functions for producing (1) the NI 113.4, 142.1, 149.3, and 174.3nm emissions from N2 and (2) the OI 130.4 and OI 135.6nm, and OII 102.5nm from O2.