Atomic data and spectral line intensities for FeVIII

Electron impact collision strengths, energy levels, oscillator strengths an d spontaneous radiative decay rates are calculated for Fe VIII. The configu rations used are 3p(6)3d, 3p(5)3d(2), 3p(6)4s, 3p(6)4p, and 3p(5)3d4s givin g rise to 73 fine-structure levels in intermediate coupling. Collision stre ngths are calculated at four incident energies, 10, 30, 50, and 70 Ry. Exci tation rate coefficients are calculated by assuming a Maxwellian electron v elocity distribution at an electron temperature of log T-e(K) = 5.57, corre sponding to maximum abundance of Fe VIII. Using the excitation rate coeffic ients and the radiative transition rates, statistical equilibrium equations for level, populations are solved at electron densities 10(8)-10(14) cm(-3 ). Relative spectral line intensities are calculated. Proton excitation rat es and solar blackbody radiative excitation are also included in the statis tical equilibrium equations. (C) 2000 Academic Press.