SIMBAD references

The chemical evolution of the disk of our Galaxy is studied with numerical models assuming infall. Several recent (and older) ideas concerning the radial dependence of the star formation rate in disk galaxies are tested, as well as a possible radial dependence of the infall time-scale.
Result. are compared to a "minimal set" of observables, including those of the solar neighborhood. Among them, the recent evidence for a negligible oxygen gradient in the outer Galaxy constrains severely some of the suggested star formation rates. On the basis of our results we propose a model with a minimal set of physically plausible assumptions that satisfies the observational constraints.