2015/02/23 by Theo Le Bret, Andrew Pontzen, Andrew P. Cooper +7
Physics and Astronomy · #Astronomy #Astrophysics #Astrophysics and Star Formation Studies #Dark matter #Dark matter halo #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Milky Way #Physics #Population #Star formation #Stars #Stellar, planetary, and galactic studies #astro-ph.GA
paper · pdf · doi:10.1093/mnras/stx552
10 pages, 6 figures
arxiv created 2015/02/23 · openalex created_date 2016/06/24 · openalex publication_date 2017/03/07 · arxiv updated 2020/03/18 · openalex updated_date 2026/08/06
We establish a controlled comparison between the properties of galactic stellar haloes obtained with hydrodynamical simulations and with ‘particle tagging’. Tagging is a fast way to obtain stellar population dynamics: instead of tracking gas and star formation, it ‘paints’ stars directly on to a suitably defined subset of dark matter particles in a collisionless, dark-matter-only simulation. Our study shows that ‘live’ particle tagging schemes, where stellar masses are painted on to the dark matter particles dynamically throughout the simulation, can generate good fits to the hydrodynamical stellar density profiles of a central Milky Way-like galaxy and its most prominent substructure. Energy diffusion processes are crucial to reshaping the distribution of stars in infalling spheroidal systems and hence the final stellar halo. We conclude that the success of any particular tagging scheme hinges on this diffusion being taken into account, and discuss the role of different subgrid feedback prescriptions in driving this diffusion.