RF discharge generation of I atoms in CH3I and CF3I for COIL/DOIL

A cw/pulsed radiofrequency discharge coupled by electrodes in coaxial arrangement was used to dissociate iodine atoms from CH3I or CF3I molecules diluted in a carrier gas (a mixture of Ar and He). The discharge chamber was arranged directly inside an iodine injector (made of aluminum) to minimize the recombination of generated atomic iodine and enabling an increased assistance of UV light for a photo-dissociation enhancement of I atoms production. The effluent of the discharge chamber/iodine injector was injected into the flow of N2 downstream the nozzle throat. Measurements of I atoms concentration distribution at different distances from the injection and in two directions across cavity were done by means of absorption measurements at the wavelength of 1315 nm. Dependences of atomic iodine concentration on main RF discharge parameters and flow mixing conditions were measured. This novel method could be an alternative to the chemical generation of atomic iodine and also an efficient alternative to other electric discharge methods of I atoms generation for chemical oxygen-iodine laser (COIL) and discharge oxygen-iodine laser (DOIL).