Galacticus: A Semi-Analytic Model of Galaxy Formation

TL;DR

Galacticus is an open-source, modular semi-analytic model for galaxy formation that simulates galaxy evolution within dark matter halos and aligns well with observational data.

Contribution

It introduces a flexible, expandable framework for galaxy formation modeling, enabling detailed exploration of physical processes and convergence testing.

Findings

Model agrees with multiple observational datasets

Demonstrates numerical convergence

Shows potential for extracting detailed galaxy evolution information

Abstract

We describe a new, free and open source semi-analytic model of galaxy formation, Galacticus. The Galacticus model was designed to be highly modular to facilitate expansion and the exploration of alternative descriptions of key physical ingredients. We detail the Galacticus engine for evolving galaxies through a merging hierarchy of dark matter halos and give details of the specific implementations of physics currently available in Galacticus. Finally, we show results from an example model that is in reasonably good agreement with several observational datasets. We use this model to explore numerical convergence and to demonstrate the types of information which can be extracted from Galacticus.