The application of a VUV-FT spectrometer and synchrotron radiation source to measurements of the NO and O2 bands at 295 K

Abstract

Current research on the Earth's upper atmosphere requires molecular parameters of unprecedented detail and accuracy. Models of the vacuum-ultraviolet (VUV) absorbing properties of the atmosphere call for absorption cross sections with details on the scale of the Doppler linewidths. As a consequence, spectroscopic data at resolving powers of the order of 106 are needed. Current particular needs are for ultra high resolution absorption cross section data for some bands of NO and OZ in the UV to VUV region. To meet these requirements, we moved the VUV Fourier transform spectrometer at Imperial College, London to a synchrotron radiation facility (Photon Factory, KEK, Japan) and measured VUV photoabsorption cross sections of NO from 195 to 160 nm and OZ from 185 to 175 nm.