H2O Collisional Broadening Coefficients at 1.37 µm and Their Temperature Dependence: A Metrology Approach

We report self- and air collisional broadening coefficients for the H2O line at 7299.43 cm?1 corresponding temperature a range spanning 293–573 K. New laser spectroscopic setups specifically designed this purpose have been developed are described. The parameters reported here in good agreement with those values HITRAN 2020 database, but uncertainties reduced by factors of about 4, 1.3 4.4 self-broadening coefficient, coefficient exponent broadening, respectively. Further, we combined our measurement approach metrological data quality objectives, addressing traceability results to international system units (SI) evaluated following guide expression uncertainty (GUM).