Soft-x-ray amplification in lithiumlike Al xi (154 Å) and Si xii (129 Å)

Recent experiments on soft-x-ray amplification in lithiumlike ions in a CO2 laser-produced recombining plasma in a magnetic field are presented. The maximum gain–length (GL) products observed are GL ≃ 3–4 for confined the 154-Å 4f–3d transition in Al xi and GL ≃ 1–2 for the 129-Å 4f–3d transition in Si xii. A one-dimensional hydrodynamic code with a collisional-radiative atomic model was used to model the plasma, and the theoretical of gain agree well with the observations. Descriptions of both hydrodynamic and atomic physics codes predictions are given.