Angular momentum, accretion and radial flows in chemodynamical models of spiral galaxies

TL;DR

This paper presents a model linking gas accretion, radial flows, and chemical evolution in spiral galaxies, emphasizing the importance of angular momentum and boundary conditions in shaping abundance gradients.

Contribution

It introduces a consistent algorithm to compute accretion profiles, radial flows, and abundance gradients, with applications to the Milky Way.

Findings

Abundance gradients depend strongly on the angular momentum of accreting gas.

Boundary conditions significantly influence outer galaxy abundance gradients.

Radial flows driven by accretion impact chemical evolution models.

Abstract

Gas accretion and radial flows are key ingredients of the chemical evolution of spiral galaxies. They are also tightly linked to each other (accretion drives radial flows, due to angular momentum conservation) and should therefore be modelled simultaneously. We summarise an algorithm that can be used to consistently compute accretion profiles, radial flows and abundance gradients under quite general conditions and we describe illustrative applications to the Milky Way. We find that gas-phase abundance gradients strongly depend on the angular momentum of the accreting material and, in the outer regions, they are significantly affected by the choice of boundary conditions.