MEASUREMENT OF THE LY-ALPHA MG RESONANCE WITH THE 2S-]3P NE-LIKE GE LINE

Measurements and calculations of the resonance between the Ly-alpha line of magnesium and the 2s --> 3p transition in neonlike germanium are presented. This resonance is of possible use as part of a resonantly photo-pumped x-ray laser scheme recently proposed which would lase on several 2p --> 2s transition between 64 and 89 angstrom in neonlike germanium. Measurements of the resonance are made by three different approaches: one using the electron beam ion trap, the second using laser-produced plasma, and the third on a tokamak. These results are compared with calculations and other measurements. Certain discrepancies are observed with previous measurements which may be due to the partial overlap between oxygenlike and neonlike lines in germanium. The results do show a good resonance between magnesium and germanium, with the germanium line between the two Ly-alpha components of magnesium but nearer to the short-wavelength component.