Measurements and theoretical estimation of N2-broadening and -shifting coefficients of the water vapor spectral lines in the 22,330-22,590 cm−1 region

Abstract

The water vapor line broadening and shifting coefficients for 36 strongest water vapor lines in the 22,330-22,590 cm−1 spectral region (6ν1+ν3 and 7ν1 bands) induced by nitrogen pressure have been measured with a spectral resolution of 0.1 cm−1 at room temperature by a Fourier transform spectrometer using a high luminance LED source. A high signal-to-noise ratio (S/N ≈ 10 000) allows one to analyze the lines with intensities from 1.25 × 10−25 to 1.15 × 10−26 cm/molecule. The N2-broadening and shifting coefficients have been calculated by a semi-empirical approach that estimates the line profiles based on anharmonic wave functions; this method explicitly takes into account all scattering channels induced by collisions.