Diffusion in the Dartmouth/Yale Stellar Evolution Code

Brian Chaboyer

Abstract. I will discuss the treatment of microscopic diffusion in the stellar evolution code which was developed at Yale (YREC). Different versions of the code are now used at a number of institutions, including Dartmouth, Ohio State, Saint Mary's, Yonsei and McMaster, but all include the same treatment of diffusion. The code allows for the treatment of helium and metal diffusion (Z), following the prescriptions of Thoul, Bahcall & Loeb (1994).