High-accuracy 12C16O2 line intensities in the 2 μm wavelength region measured by frequency-stabilized cavity ring-down spectroscopy

Reported here are highly accurate, experimentally measured ro-vibrational transition intensities for the R-branch of the (20012)-(00001) (CO2)-C-12-O-16 band near lambda =2 mu m. Measurements were performed by a frequency-stabilized cavity ring-down spectroscopy (FS-CRDS) instrument designed to achieve precision molecular spectroscopy in this important region of the infrared. Through careful control and traceable characterization of CO2 sample conditions, and through high-fidelity measurements spanning several months in time, we achieve relative standard uncertainties for the reported transition intensities between 0.15% and 0.46%. Such high accuracy spectroscopy is shown to provide a stringent test of calculated potential energy and ab initio dipole moment surfaces, and therefore transition intensities calculated from first principles. Published by Elsevier Ltd.