Short wavelength laser calculations for electron pumping in neon-like krypton (Kr XXVII)

Abstract
We present calculations of electron impact collision strengths and spontaneous radiative decay rates for neon-like krypton (Kr XXVII) for the 2s22p6, 2s22p53s, 2s22p53p, and 2s22p53d configurations. From these atomic data the level populations as a function of the electron density were calculated at two temperatures (Te=1×107 K and Te=3×107 K). The analysis of level populations shows that a volume of krypton in which a significant number of the ions are in the Kr XXVII degree of ionization can produce a significant gain in transitions between the 2s22p53s and 2s22p53p configurations. At an electron density of 1×1019 cm−3 the plasma length has to be on the order of 1 m; at a density of 1×1021 cm−3 the length is reduced to about 0.5 cm; and at an electron density of 1×1022 cm−3 the length of the plasma is further reduced to about 1 mm.