Diffusion in barred-spiral galaxies

TL;DR

This paper investigates how stars migrate radially in barred-spiral galaxies by analyzing diffusion coefficients and timescales, revealing that diffusion varies over time and peaks near corotation and outer disk regions.

Contribution

It introduces a method to quantify stellar radial migration in self-consistent galaxy models, linking diffusion to bar evolution and asymmetric pattern development.

Findings

Diffusion varies with the evolution of the galactic bar.

Maximum diffusion occurs near corotation and in the outer disk.

Diffusion is not constant but follows the bar's dynamics.

Abstract

We characterize the radial migration of stars in the disk plane by calculating the diffusion coefficient and the diffusion time-scale for a bulge-disk N-body self-consistent system with a marginally-stable Toomre-Q parameter. We find that diffusion is not constant in time, but follows the evolution of the bar, and becomes maximum near the corotation region and in the external disk region, where asymmetric patterns develop.