9319034 Ferland Emission line regions define the end points of stellar evolution and are present in the most luminous objects in the universe (the distant quasars). Detailed understanding of this gas requires reference to large- scale numerical simulations. This project will continue developing a computer program which simulates the physical conditions within a non-equilibrium plasma and predicts its spectrum. Several broad problems in active galactic nuclei, H II regions, and classical novae will be investigated . The emission line clouds of high redshift quasars have metallicities approaching 10 times solar, similar to those found in the cores of massive galaxies at similar epochs, and this metallicity correlates with luminosity and/or redshift. This work will probe galactic chemical evolution at large redshift. A second area to be investigated will involve an attempt to understand physical conditions within galactic H II regions and surrounding photodissociation regions. This will lead to a more complete understanding of measurements of galactic abundance gradients. Another area will be classical novae, to better constrain the mass and abundances of the ejecta, and thereby their contribution to galactic nucleosynthesis. ******
