Temperature- and pressure-dependent absorption coefficients for CO2 and O2 at 193 nm

Absorption of laser radiation at 193 nm by CO₂ and O₂ was studied at a series of different temperatures up to 1273 K and pressures up to 1 bar. The spectrum for CO₂ was found to be broadband, so that absorption could be fitted to a Beer-Lambert law. On the other hand, the corresponding O₂ spectrum is strongly structured and parameterisation requires a more complex relation, depending on both temperature and the product (pressure 2 absorption path length). In this context, the influence of spectral structure on the resulting spectrally integrated absorption coefficients is discussed. Using the fitting parameters obtained, effective transmissions at 193 nm can be calculated for a wide range of experimental conditions. As an illustration of the practical application of these data, the calculation of effective transmission for a typical industrial flue gas is described.