The Galactic Lithium Evolution Revisited

Abstract

The evolution of the 7Li abundance in the Galaxy has been computed by taking into account several 7Li sources: novae, massive AGB stars, C-stars, Type II SNe and GCRs. The theoretical predictions for the evolution of the 7Li abundance in the solar neighborhood have been compared to a new compilation of data. A critical analysis of extant observations revealed a possible extension of the Li plateau towards higher metallicities (up to [Fe/H] = -0.5 or even -0.3) with a steep rise afterwards. We conclude that 1) the 7Li contribution from novae is required in order to reproduce the shape of the growth of A(Li) versus [Fe/H], 2) the contribution from Type II SNe should be lowered by at least a factor of two, and 3) the 7Li production from GCRs is probably more important than previously estimated, in particular at the highest metallicities.