Abstract: A method of identifying and determining the concentrations of multiple species in a gas sample, includes providing a spectrophone assembly having a detector chamber, supplying the gas sample to the detector chamber and simultaneously passing a plurality of radiations of different wavelengths into the detector chamber to produce multiple acoustic resonances of different frequencies. Acoustic resonances in the detector chamber are simultaneously sensed to produce corresponding electrical signals, and the electrical signals are analysed to identify the species present in the gas sample and determine the concentration of each specie.

Abstract: A method of identifying and determining the concentrations of multiple species in a gas sample, includes providing a spectrophone assembly having a detector chamber, supplying the gas sample to the detector chamber and simultaneously passing a plurality of radiations of different wavelengths into the detector chamber to produce multiple acoustic resonances of different frequencies. Acoustic resonances in the detector chamber are simultaneously sensed to produce corresponding electrical signals, and the electrical signals are analysed to identify the species present in the gas sample and determine the concentration of each specie.

Abstract: A laser device has a plasma discharge region for dissociating a diatomic gas into atoms. A nozzle connects the plasma discharge region with an optical cavity. The nozzle expands the plasma accelerating it to a supersonic velocity as it passes from the discharge region into the optical cavity. As the plasma passes through the nozzle, the dissociated atoms are recombined into molecules in a metastable energy state. The nozzle includes a gas injector for introducing a lasing gas into the plasma flow through the nozzle.