A large stellar evolution database for population synthesis studies. III. Inclusion of the full asymptotic giant branch phase and Web tools for stellar population analyses

Stellar evolution tracks and isochrones are key inputs for a wide range of astrophysical studies; in particular, they are essential to the interpretation of photometric and spectroscopic observations of resolved and unresolved stellar populations. We have made available to the astrophysical community a large, homogenous database of up-to-date stellar tracks and isochrones and a set of programs useful in population synthesis studies. In this paper we first summarize the main properties of our stellar model database (BaSTI) already introduced by Pietrinferni and coworkers. We then discuss an important update of the database, i.e., the extension of all stellar models and isochrones until the end of the thermal pulses along the asymptotic giant branch. This extension of the library is particularly relevant for stellar population analyses in the near-infrared or longer wavelengths, where the contribution to the integrated photometric properties by cool and bright asymptotic giant branch stars is significant. A few comparisons with empirical data are also presented and briefly discussed. We then present three Web tools that allow an interactive access to the database and make it possible to compute user-specified evolutionary tracks, isochrones, stellar luminosity functions, and synthetic color-magnitude diagrams and integrated magnitudes for arbitrary star formation histories. All these Web tools are available at the BaSTI database official Web site.