High resolution diode laser spectroscopy of H₂O spectra broadened by nitrogen and noble gases

Abstract

The absorption spectra of pure H 2 O with mixtures of broadening gases N 2 , Ar, Xe, He, Ar and air have been measured in 1.39 mµ spectral region by high resolution spectrometer based on diode laser (DFB NEL, Japan). For the processing of pure water spectra and it's mixtures with a different broadening gases in a wide pressure range we used a multispectrum fitting procedure developed at IAO. The program is based on a relatively simple Rautian-Sobel'man line profile and linear pressure dependence of the line profile parameters. H 2 O measured spectra bulk processing results in the retrieving of such line parameters: zero-pressure line center positions, intensities, self-broadening and self-shift coefficients of pure water, broadening and shift coefficients for other gases which are describes the experiment with the minimum residuals in a wide pressure range.