Excitation of a helium-potassium mixture in a pulsed hollow-cathode discharge

Concentrations of the excited levels of He (principal quantum number n = 2, 3, 4) in a pulsed hollow-cathode discharge have been determined experimentally for pure helium and for a mixture with potassium vapors with a density of up to 10 to the 16th per cu cm. For a He pressure of 533 Pa, a supply voltage of 3 kV, and a discharge current of 200 A (peak), the populations of the singlet levels 2(1)S and 2(1)P and triplet levels 2(3)S and 2(3)P are estimated at 10 to the 11th and 10 to the 12th per cu cm, respectively. The possibility of using a pulsed hollow-cathode discharge to obtain high populations of highly excited (20 keV or greater) atomic levels is demonstrated.