Characteristic Features of Energy Transfer in the Wall Region of a Lithium Vapor Discharge

A series of experiments with a fully ionized turbulent lithium plasma is described. Discharges with a heat flux density onto the wall of 1–3kW/cm[sup 2] and an electron density of ?10[sup 15]cm[sup –3] are obtained. The energy can be transferred to the wall by both Li[sup +] and Li[sup ++] ions. The measurements show that the photon flux corresponding to the main resonant transition of lithium atoms is a factor of 10[sup 4]–10[sup 5] less than it could be if all the ions arriving at the wall recombined there. A mechanism is proposed for energy transfer onto the wall via the recombination of Li[sup ++] ions to Li[sup +] ions in the cold wall region of the discharge and the subsequent energy emission by Li[sup +] ions.