Realistic simulated galaxies form [$\alpha$/Fe]-[Fe/H] knees due to a sustained decline in their star formation rates

Andrew C. Mason, Robert A. Crain, Ricardo P. Schiavon +5

We examine the stellar [$\alpha$/Fe]-[Fe/H] distribution of $\simeq 1000$ present-day galaxies in a high-resolution EAGLE simulation. A slight majority of galaxies exhibit the canonical…