Metallicity Gradients in Simulated Disk Galaxies

TL;DR

This paper analyzes metallicity and abundance ratio gradients in simulated disk galaxies, showing how these gradients evolve over time and are affected by stellar migration, with implications for understanding galaxy evolution.

Contribution

It presents detailed simulation results on metallicity gradients and their evolution, highlighting the impact of stellar migration on observed gradients.

Findings

Gradients flatten over 1-3 scalelengths with time.

Radial migration flattens intrinsic metallicity gradients.

[O/Fe] gradient remains robust against migration.

Abstract

The stellar metallicity and abundance ratio gradients from the fiducial late-type galaxy simulation of Stinson et al. (2010) are presented. Over 1-3 scalelengths, gradients are shown to flatten with time, consistent with empirical evidence at high- and low-redshifts. Kinematic effects, including radial migration, though, flatten these intrinsicly steep gradients such that by redshift z=0, the measured gradients of these (now) old stars are flatter than their young counterparts, in contradiction to what is observed locally. Conversely, the stellar [O/Fe] gradient is (to first order) robust against migration, remaining fairly flat for both young and old populations today.