The Three Hundred Project: the evolution of galaxy cluster density profiles

Mostoghiu, Robert; Knebe, Alexander; Cui, Weiguang; Pearce, Frazer R.; Yepes, Gustavo; Power, Chris; Dave, Romeel; Arth, Alexander

Abstract

Recent numerical studies of the dark matter density profiles of massive galaxy clusters (Mhalo > 1015 M) show that their median radial mass density profile remains unchanged up to z > 1, displaying a highly self-similar evolution. We verify this by using the data set of theThe Three Hundred project, i.e. 324 cluster-sized haloes as found in full physics hydrodynamical simulations. We track the progenitors of the mass-complete sample of clusters at z = 0, and find that their median shape is already in place by z = 2.5. However, selecting a dynamically relaxed subsample (∼16 per cent of the clusters), we observe a shift of the scale radius rs towards larger values at earlier times. Classifying the whole sample by formation time, this evolution is understood as a result of a two-phase halo mass accretion process. Early-forming clusters – identified as relaxed today – have already entered their slow accretion phase, hence their mass growth occurs mostly at the outskirts. Late-forming clusters – which are still unrelaxed today – are in their fast accretion phase, thus the central region of the clusters is still growing. We conclude that the density profile of galaxy clusters shows a profound self-similarity out to redshifts z ∼ 2.5. This result holds for both gas and total density profiles when including baryonic physics, as reported here for two rather distinct sub-grid models.

Citation

Mostoghiu, R., Knebe, A., Cui, W., Pearce, F. R., Yepes, G., Power, C., …Arth, A. (2018). The Three Hundred Project: the evolution of galaxy cluster density profiles. Monthly Notices of the Royal Astronomical Society, 483(3), 3390-3403. https://doi.org/10.1093/mnras/sty3306

• Journal Article Type: Article
• Acceptance Date: Dec 6, 2018
• Online Publication Date: Dec 6, 2018
• Publication Date: Dec 6, 2018
• Deposit Date: Dec 21, 2018
• Publicly Available Date: Dec 21, 2018
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Oxford University Press
• Peer Reviewed: Peer Reviewed
• Volume: 483
• Issue: 3
• Pages: 3390-3403
• DOI: https://doi.org/10.1093/mnras/sty3306
• Keywords: Space and Planetary Science; Astronomy and Astrophysics
• Public URL: https://nottingham-repository.worktribe.com/output/1437310
• Publisher URL: https://academic.oup.com/mnras/advance-article/doi/10.1093/mnras/sty3306/5232383
• Additional Information: This article has been accepted for publication in Monthly Notices of the Royal Astronomical Society ©: 2018 The Authors Published by Oxford University Press on behalf of the Royal Astronomical Society. All rights reserved.