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arXiv · 2511.00240

A Milky Way mass model for isolated simulations

J A Sellwood
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Abstract

This paper presents an equilibrium model of a Milky Way-like spiral galaxy that supports open, mostly 2- and 3-arm spiral patterns but does not form a bar. It is suggested as a more realistic alternative model to that employed by the Agora collaboration; their model has a much lower disk mass and therefore forms only multi-arm spiral patterns. This improved model should enable simulations that test star-formation and feedback models in a more realistic isolated galaxy. Three versions of the same model having $2.1\times 10^5$, $2.1\times 10^6$, and $2.1\times 10^7$ particles are available for download.

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J A Sellwood. 2025-10-31. A Milky Way mass model for isolated simulations. https://arxiv.org/abs/2511.00240

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