Line-shape study of CO perturbed by N${}_2$ with mid-infrared frequency comb-based Fourier-transform spectroscopy

We developed a mid-infrared optical frequency comb-based Fourier-transform spectrometer and performed a line-shape study of the fundamental vibrational band of CO perturbed by N${}_2$, which is crucial for atmospheric science and astronomical observations. The comb-based FTS enabled us to measure the whole vibrational band with high resolution and precision at several pressures between 10 and 400 Torr. Observed absorption profiles were fitted with the speed-dependent Voigt profile. Collisional broadening, speed-dependent collisional width and shift coefficients are derived. The reliability of our results is established from considerations of systematic errors and comparison with previous studies.