On star formation and chemical evolution in the Galactic disc

TL;DR

This paper models the chemical evolution of the Galactic disc, examining how different star formation laws and infall timescales affect metallicity gradients and gas distribution, highlighting challenges in simultaneously reproducing observations.

Contribution

It evaluates various star formation laws within chemical evolution models to understand their impact on Galactic disc properties, emphasizing the need for improved modeling approaches.

Findings

Only some SF laws reproduce the metallicity gradient.

An inside-out infall scenario is necessary for accurate modeling.

Current models struggle to match both metallicity and gas distribution observations.

Abstract

The abundance gradients and the radial gas profile of the Galactic disc are analysed by means of a model for the chemical evolution of galaxies. As one of the major uncertainties in models for galaxy evolution is the star formation (SF) process, various SF laws are considered,to assess the response of model predictions to the different assumptions. Only some SF laws are successful in reproducing the metallicity gradient, and only if combined with a suitable infall timescale increasing outward (inside-out formation scenario). Still, it is difficult to reproduce at the same time also the observed gas distribution; we therefore suggest further improvements for the models.