We present the results of the spectral line-shape study of the first measurement of the extremely weak (7–0)
band of the 12C16O molecule. Measurements were done with a highly sensitive cavity ring-down spectrometer.
Collisional narrowing, analyzed in terms of speed-dependent effects, was observed for the first time for
transitions with line intensities below 2 ⋅ 10−29 cm/molecule at 296 K. We provide a full set of line-shape
parameters of the speed-dependent and regular Voigt profile analysis for 14 transitions from P and R branches.
Experimental verification of a strong vibrational dependence of the pressure shifting described by the Hartmann
model (Hartmann, 2009) is extended up to the sixth overtone highly sensitive to the model parameter.
Subject:Carbon monoxide, Cavity ring-down spectroscopy, High resolution molecular spectroscopy, Spectral line shapes, Pressure broadening and shifting, Speed-dependent effects