ATOMIC DATA AND SPECTRAL-LINE INTENSITIES FOR C-LIKE MG-VII

Electron impact collision strengths and spontaneous radiative decay rates are calculated for the C-like ion Mg VII. The data pertain to the 46 levels of the configurations 2s(2)2p(2), 2s2p(3), 2p(4), 2s(2)2p3S, 2s(2)2p3p, and 2s(2)2p3d, Collision strengths are calculated at three incident electron energies: 12.0, 24.0, and 36.0 Ry. Spectral line intensities are calculated for all transitions with intensities within two orders of magnitude of the most intense Mg VII line. These are obtained by computing the excitation rate coefficients (cm(3) s(-1)), i.e., the collision strengths integrated over a Maxwellian electron distribution, and then solving the equations of detailed balance for the populations of the 46 energy levels, assuming a collisional excitation model and an electron temperature of 6.31 X 10(5) K. This temperature is typical for Mg VII in solar and some other astrophysical plasmas. Using the excitation rate coefficients and the radiative decay rates, level populations are computed for several electron densities and are also given in this paper. (C) 1995 Academic Press. Inc.