Modelling the tightest relation between galaxy properties and dark matter halo properties from hydrodynamical simulations of galaxy formation

He, Jian-hua

Abstract

We investigate how a property of a galaxy correlates most tightly with a property of its host dark matter halo, using state-of-the-art hydrodynamical simulations of galaxy formation: EAGLE, Illustris, and IllustrisTNG. Unlike most of the previous work, our analyses focus on all types of galaxies, including both central and satellite galaxies. We find that the stellar mass of a galaxy at the epoch of the peak circular velocity with an evolution correction gives the tightest such correlation to the peak circular velocity Vpeak of the galaxy’s underling dark matter halo. The evolution of galaxy stellar mass reduces rather than increases scatter in such a relation. We also find that one major source of scatter comes from star stripping due to the strong interactions between galaxies. Even though, we show that the size of scatter predicted by hydrodynamical simulations has a negligible impact on the clustering of dense Vpeak-selected subhalo from simulations, which suggests that even the simplest subhalo abundance matching (SHAM), without scatter and any additional free parameter, can provide a robust prediction of galaxy clustering that can agree impressively well with the observations from the Sloan Digital Sky Survey (SDSS) main galaxy survey.

Citation

He, J. (2020). Modelling the tightest relation between galaxy properties and dark matter halo properties from hydrodynamical simulations of galaxy formation. Monthly Notices of the Royal Astronomical Society, 493(3), 4453-4462. https://doi.org/10.1093/mnras/staa620

• Journal Article Type: Article
• Acceptance Date: Feb 26, 2020
• Online Publication Date: Mar 4, 2020
• Publication Date: Apr 30, 2020
• Deposit Date: Apr 29, 2020
• Publicly Available Date: Apr 29, 2020
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 493
• Issue: 3
• Pages: 4453-4462
• DOI: https://doi.org/10.1093/mnras/staa620
• Public URL: https://durham-repository.worktribe.com/output/1265239