Cavity ringdown spectroscopy measurements of the infrared water vapor continuum

Abstract

The measurements of the water vapor continuum were analyzed using infrared cavity ringdown spectroscopy (CRDS) at frequencies of 931.002, 944.195 and 969.104 cm-1. The experiments uses a continuous-wave CO2 laser and an acousto-optic modulator to create laser pulses which are injected into a 100 cm long near-confocal ringdown cavity. It is found that the far wings of water vapor lines are the primary agent responsible for the water vapor continuum.