Recombination in Xenon and Krypton Afterglows†

Electron density decay was studied in the afterglow of pulsod electrodeless microwave discharges in krypton and xenon using 3 cm equipment. Each gas contained an unknown impurity of not more than 0-5% of the other. Gas pressure was variod from 3 to 30 mm Hg and ionizing pulse power from 1-5 to 22-5 kw. The xenon afterglow was unaffected by the krypton impurity at pressures above 5 mm Hg and lod to a recombination coefficient of 23 x 10−1 cm3 ion sec at 10 mm Hg. This coefficient increased with pressure above 10 mm Hg, probably caused by pressure limitations on tho microwave method. It is suggested that the krypton afterglow was greatly affected by charge transfer to the xenon impurity. A recombination coefficient of not greater than ion 1. 1×10−6 sec is deduced for krypton.