The Effects of an Early Galactic Wind on the Evolution of D,3He, and Z

The predictions of the abundances of D and \he3 from Big Bang Nucleosynthesis(BBN) and recent observations of these two isotopes suggest the need to developnew chemical evolution models. In particular, we examine the role of an earlyepisode of massive star formation that would induce a strong destruction of Dand a galactic wind. We discuss the ability of these models to match theobserved local properties of the solar neighborhood such as the gas massfraction, oxygen abundance, the age-metallicity relation, and the present-daymass function (PDMF). We also examine in detail the ability of the chemicalevolution models discussed to reproduce the apparent lack of low mass, lowmetallicity stars in the solar neighborhood, namely the G-dwarf distribution.Indeed, we find models which satisfy the above constraints while at the sametime allowing for a large primordial D/H ratio as is reportedly measured insome quasar absorption systems at high $z$, without the overproduction of heavyelements. The latter constraint is achieved by employing a simple dynamicalmodel for a galactic wind.Comment: 31 pages, latex, 15 ps figures, revised version, as acceped for publication by ApJ, all figures have been revised, qualitatively conclusions are unchange