Measurements of high‐resolution ultraviolet‐visible absorption cross sections at stratospheric temperatures: 1. Nitrogen dioxide

Abstract

A method for obtaining high‐resolution, temperature dependent absorption cross sections in the ultraviolet and visible regions is described. The technique combines a Fourier transform spectrometer with a supersonic jet expansion for sample preparation. Infrared spectroscopy is used to determine the temperature of the sample and to reveal any interferences in the ultraviolet‐visible measurement. This method is applied to the measurement of absorption cross sections of 200 ± 20 K nitrogen dioxide in the 370‐ to 497‐nm region, at resolutions of 2 and 0.5 cm −1 .