Monte Carlo simulation of radiation trapping and quenching of photofragment fluorescence after 193 nm photolysis of NaCl

Abstract

The concentration of gas-phase NaCl is measured by monitoring Na photofragment fluorescence after 193 nm excimer laser photodissociation. Radiation trapping is observed for NaCl concentrations over 20 ppm resulting in a non-linear response of fluorescence with NaCl concentration. A Monte Carlo simulation of radiation trapping and quenching is performed to model the fluorescence response and to predict fluorescence intensities under the high-pressure conditions found in coal gasification.