title: Spectroscopic measurement of the vapour pressure of ice.
abstract: We present a laser absorption technique to measure the saturation vapour pressure of hexagonal ice. This method is referenced to the triple-point state of water and uses frequency-stabilized cavity ring-down spectroscopy to probe four rotation-vibration transitions of at wavenumbers near 7180 cm(-1). Laser measurements are made at the output of a temperature-regulated standard humidity generator, which contains ice. The dynamic range of the technique is extended by measuring the relative intensities of three weak/strong transition pairs at fixed ice temperature and humidity concentration. Our results agree with a widely used thermodynamically derived ice vapour pressure correlation over the temperature range 0°C to -70°C to within 0.35 per cent.
authors.affiliation: Instytut Fizyki, Uniwersytet Mikołaja Kopernika, ul. Grudziadzka 5/7, 87-100 Toruń, Poland.
authors.forename: K
authors.initials: K
authors.lastname: Bielska
authors.forename: D K
authors.initials: DK
authors.lastname: Havey
authors.forename: G E
authors.initials: GE
authors.lastname: Scace
authors.forename: D
authors.initials: D
authors.lastname: Lisak
authors.forename: J T
authors.initials: JT
authors.lastname: Hodges