Vol. 30, issue 12, article # 4

Abstract:

Absorption spectra of methane in the 11000–11400 cm^–1 region were recorded at a IFS–125M Fourier spectrometer at pressures from 11 to 100 mbar, room temperature, and spectral resolution of 0.03 cm^–1. A multipass cell 60 cm long and 44 passes were used, which provided a total path length of 2640 cm and threshold sensitivity to absorption on an order of 10^–8 cm^–1. Voight contour parameters (line center, intensity, self-broadening and self-shift coefficients) were determined.

Keywords:

methane, Fourier spectrometer, absorption, line strength, halfwidth, line shift

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