The surface chemistry of stars. I - Diffusion of heavy ions in white dwarf envelopes. II - Fractionated accretion of interstellar matter

Abstract

The diffusion separation of heavy elements in the envelopes of white dwarfs is examined. Consideration is given to the physics of diffusion with particular reference to the conditions in white dwarfs. A solution of the diffusion equation that includes the effects of convection and accretion is presented.