SPECTROSCOPIC ANALYSIS OF VISIBLE AND NEAR UV-LIGHT EMITTED IN 120-KEV KR8+-HE AND KR8+-H2 COLLISIONS

A spectroscopic analysis of light in the 2000-6000 angstrom wavelength range emitted by Kr7+ and Kr6+ ions after charge exchange in 120-keV Kr8+-He and Kr8+-H-2 collisions is performed. Transitions with DELTA-n = 0 and DELTA-n = 1 for n = 6 and 7 states of Kr VIII following single electron capture are identified and their emission cross sections are determined. Fine structure splittings of the 3d(10)6p2P, 3d(10)6d2D and 3d(10)6f2F terms are measured and compared with theoretical predictions. As in Ar8+-He and Ar8+-H-2 collisions, strong lines due to double electron capture are observed both in Kr8+-He and Kr8+-H-2 collisions. They are identified as Rydberg transitions of the type 4snl-4sn'l' in Kr VII.