A collisional-radiative model for simulation of Ne-like and F-like resonance lines emitted from laser produced plasmas

We describe a collisional radiative code to simulate the Ne-like and F-like resonance lines emitted from laser produced plasmas. Ions and excited levels densities are calculated by solving rate equations using an implicit-finite difference method for steady state, quasi steady state and time-dependent conditions. The code calculates intensities of Ne-like 1s22s22p6 → 1s22s22p5nl and F-like 1s22s22p5 → 1s22s22p4nl resonance lines emitted from various species, Z = 18 to 32, i.e., from argon to germanium. Intensities of photons emitted between Ne-like 1s22s22p5n′l′ → 1s22s22p5nl and F-like 1s22s22p4n′l′ → 1s22s22p4nl excited levels are also calculated. Doppler broadened line shapes are assumed. Absorption of resonance lines is determined using an escape factor approximation. The ratios of optically thin various F-like to Ne-like resonance lines are calculated with the aim that such ratios can serve as a diagnostic to measure electron temperatures.  2004 Elsevier B.V. All rights reserved.