The CARMA Project — Towards Convergence of Galaxy Formation Models

Fabrice Durier (Steward Observatory)

May 19, 2016

–

Abstract: Over the past two decades, cosmological hydrodynamic simulations have evolved into powerful tools for testing our understanding of the evolution of the cosmic structures. Nonetheless, existing computational limitations still require simulations to rely on phenomenological approaches when critical phenomena, such as star formation or feedback processes, involve scales that are far below resolution limits. As a workaround, several research teams (MAGICC, OWLS, EAGLE, Illustris, FIRE, etc.) have developed their own algorithms to model sub-grid processes. Although considerable effort has been gone into calibrating the intrinsic parameters of individual implementations, very little work has been done, to date, to systematically compare models that are often very different both conceptually and in their numerical implementations. The CARMA project aims to fill this gap. We have carried out a fair comparison of some of the most well established models of galaxy formation in order to identify their strengths and weaknesses. In this presentation, I will show preliminary results for a selection of models and review briefly how their predictions of galaxy population properties compare to observational constraints. Then, focusing on the properties of the various baryon phases and cosmic flows, I will show how the metal enrichment history of these phases can help identify where the model results show convergence and where they differ from each other.