Diffusion in the CESAM code

Yveline Lebreton

Abstract. I shall present the main aspects of the implementation of microscopic diffusion processes in the French public stellar evolution code CESAM (Morel 1997) : equations and their inputs and numerics. In CESAM two formalisms have been implemented : the simplified Michaud and Proffitt (1993) formalism in which heavy elements are treated as trace elements and a general formalism based on Burger's equations.