We investigate the variation of species densities and electric field along a static model coronal loop consisting of electrons, protons, and heavier ions in a gravitationally stratified stellar atmosphere in an attempt to relate photospheric and coronal loop abundances. The loop plasma is assumed to be confined along a strong magnetic field line, so all forces transverse to the magnetic field are taken to be in balance and the loop can be modeled as a one-dimensional structure. Differential gravitational stratification of the ion species induces a polarization electric field along the loop. By invoking charge quasi-neutrality, we devise an iteration scheme to compute numerical solutions for the species densities and to prescribed accuracy; we also derive approximate analytic solutions. For confined coronal plasma loops that are sufficiently long lived for gravitational settling to occur (e.g., 1 day), severe reduction in coronal ion densities would be expected. Our self-consistent, multicomponent treatment predicts higher loop densities than those predicted by a model that neglects the effect of the heavy ions on the electric field; the density enhancement is an increasing function of the distance along the loop and of the ion charge and ranges from 4% for twice-ionized species to 33% for 14 times-ionized species at the top of an isothermal loop with T = 3 × 106 K and a radius of 109 cm.
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