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arXiv · 1601.04709

Semi-Analytic Galaxy Evolution (SAGE): Model Calibration and Basic Results

Darren J. Croton·Adam R. H. Stevens·Chiara Tonini·Thibault Garel·Maksym Bernyk·Antonio Bibiano·Luke Hodkinson·Simon J. Mutch·Gregory B. Poole·Genevieve M. Shattow
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Abstract

This paper describes a new publicly available codebase for modelling galaxy formation in a cosmological context, the "Semi-Analytic Galaxy Evolution" model, or SAGE for short. SAGE is a significant update to that used in Croton et al. (2006) and has been rebuilt to be modular and customisable. The model will run on any N-body simulation whose trees are organised in a supported format and contain a minimum set of basic halo properties. In this work we present the baryonic prescriptions implemented in SAGE to describe the formation and evolution of galaxies, and their calibration for three N-body simulations: Millennium, Bolshoi, and GiggleZ. Updated physics include: gas accretion, ejection due to feedback, and reincorporation via the galactic fountain; a new gas cooling--radio mode active galactic nucleus (AGN) heating cycle; AGN feedback in the quasar mode; a new treatment of gas in satellite galaxies; and galaxy mergers, disruption, and the build-up of intra-cluster stars. Throughout, we show the results of a common default parameterization on each simulation, with a focus on the local galaxy population.

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Darren J. Croton, Adam R. H. Stevens, Chiara Tonini, Thibault Garel, Maksym Bernyk, Antonio Bibiano, Luke Hodkinson, Simon J. Mutch, Gregory B. Poole, Genevieve M. Shattow. 2016-01-22. Semi-Analytic Galaxy Evolution (SAGE): Model Calibration and Basic Results. https://doi.org/10.3847/0067-0049%2F222%2F2%2F22

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