Modeling of efficient soft x-ray lasers in transitions of nickel-like and neon-like ions.

We have modeled the plasma physics and amplification process in efficient soft x-ray lasers generated by rapid heating of plasmas by a short (8 ps) optical laser pulse of $\sim $ 1 J energy impinging at grazing incidence. This geometry allows for the efficient pumping of high repetition rate soft x-ray lasers [1-3]. The two temperature model includes all hydrodynamic equations written in 1.5D, as well a complete atomic model and multi-cell radiation transport. The equations that yield a full description of the plasma are solved using a finite difference method in a Lagrangian coordinate scheme. A post processor performs ray tracing to calculate output beam characteristics and intensities. The results corresponding to lasers in the 13.9 nm line of Ni-like Ag and the 32.6 nm and 30.1 nm of Ne-like Ti are discussed in comparison with experiments. Work supported by the NSF EUV ERC, Award EEC-0310717. \newline \newline 1. R. Keenan et al, Phys. Rev. Lett., 94, 103901, (2005) \newline 2. B. M. Luther et al, Optics Lett., 30, 165, (2005) \newline 3. D. Alessi et al, Opt. Express, 13,. 2093, ( 2005)