Measurements of N2- and O2-broadening and shifting parameters of methane spectral lines in the 5550-6236 cm−1 region

The absorption spectra of mixtures of methane (CH4) with N2 and O2 at different partial pressures of both CH4 and buffer gases for three temperatures 240, 267, and 296 K have been recorded using the Bruker IFS 125 HR FTIR spectrometer in the 5550-6236 cm−1 region. The multispectrum fitting procedure has been applied to these spectra to recover the spectral line parameters. The main goal of this procedure was the determination of the N2- and O2-broadening and shifting coefficients and the exponents of their temperature dependences. These parameters have been derived for 452 assigned lines with good values of the signal to noise ratio. The rotational dependence of the mean values of these parameters is discussed. The temperature dependence exponents were observed for both N2 and O2 buffer gases.