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arXiv · 1204.1399

Gas and Metal Distributions within Simulated Disk Galaxies

B. K. Gibson·S. Courty·D. Cunnama·M. Molla
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Abstract

We highlight two research strands related to our ongoing chemodynamical Galactic Archaeology efforts: (i) the spatio-temporal infall rate of gas onto the disk, drawing analogies with the infall behaviour imposed by classical galactic chemical evolution models of inside-out disk growth; (ii) the radial age gradient predicted by spectrophometric models of disk galaxies. In relation to (i), at low-redshift, we find that half of the infall onto the disk is gas associated with the corona, while half can be associated with cooler gas streams; we also find that gas enters the disk preferentially orthogonal to the system, rather than in-plane. In relation to (ii), we recover age gradient troughs/inflections consistent with those observed in nature, without recourse to radial migrations.

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B. K. Gibson, S. Courty, D. Cunnama, M. Molla. 2012-04-06. Gas and Metal Distributions within Simulated Disk Galaxies. https://arxiv.org/abs/1204.1399

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