EVOLUTION OF BERYLLIUM ABUNDANCES IN THE GALACTIC HALO

We have used a spectrum synthesis code to measure Be abundances for three halo stars and an upper limit for a fourth. The abundances are discussed considering models for Galactic and primordial synthesis of Be. Computations for inhomogeneous big bang models range over two orders of magnitude, and we can at best place upper limits on possible primordial nucleosynthesis. We compute a new model for the evolution of Be abundances in the halo, using constraints imposed by its overall metallicity distribution. Observations of stars of [Fe/H] approximately -2.0 are required to clarify the enrichment history of this element.