A new RF plasma jet generator (DSOG-4) of singlet delta oxygen has been developed for use in an oxygen-iodine laser. Two different modes of operation were studied: (1) chilling of the plasma jet by a neutral gas stream and (2) an energy transfer from plasma jet to a neutral gas stream. The plasma jet was produced in an Al cylindrical nozzle, having the cross section of 3 mm2. The chilling mode used mixtures O2:NO to produce the plasma jet, which was subsequently chilled by He, injected at the nozzle exit. The energy transfer mode used mixtures He:NO to produce the plasma jet, which was mixed with a neutral stream of O2, allowing thus energy transfer to oxygen molecules with enhanced selectivity. The RF frequency was 99.9 MHz and the RF power was up to 200 W. Both the modes of operation were tested in a transverse flow Discharge Oxygen-Iodine Laser (DOIL). The singlet delta oxygen yield and the atomic iodine luminescence at the wavelength 1315 nm were measured. The energy transfer mode proved to be an effective alternative of the classic chilling mode. It enables new generating schemes, which may bypass some of the classic limitations in oxygen discharges.
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