From stellar haloes to intracluster light: the physics of the Intra-Halo Stellar Component in cosmological hydrodynamical simulations - INSU - Institut national des sciences de l'Univers Access content directly
Journal Articles Monthly Notices of the Royal Astronomical Society Year : 2020

From stellar haloes to intracluster light: the physics of the Intra-Halo Stellar Component in cosmological hydrodynamical simulations

Rodrigo Cañas
  • Function : Author
Claudia del P. Lagos
  • Function : Author
Pascal J. Elahi
  • Function : Author
Chris Power
  • Function : Author
Charlotte Welker
  • Function : Author

Abstract

We study the Intra-Halo Stellar Component (IHSC) of Milky Way-mass systems up to galaxy clusters in the Horizon-AGN cosmological hydrodynamical simulation. We identify the IHSC using an improved phase-space galaxy finder algorithm which provides an adaptive, physically motivated, and shape-independent definition of this stellar component, that can be applied to haloes of arbitrary masses. We explore the IHSC mass fraction - total halo's stellar mass, $f_{M_{*,\mathrm{IHSC}}} - M_{*}$ , relation, and the physical drivers of its scatter. We find that on average, the $f_{M_{*,\mathrm{IHSC}}}$ increases with total stellar mass, with the scatter decreasing strongly with mass from 2 dex at $M_{*,\mathrm{tot}}\simeq 10^{11}\, \mathrm{M}_\odot$ to 0.3 dex at group masses. At high masses, $M_{*,\mathrm{tot}} 10^{11.5}\, \mathrm{M}_\odot$ , $f_{M_{*,\mathrm{IHSC}}}$ increases with the number of substructures, and with the mass ratio between the central galaxy and largest satellite, at fixed M*, tot. From mid-size groups and systems below $M_{*,\mathrm{tot}} 10^{12}\, \mathrm{M}_\odot$ , we find that the central galaxy's stellar rotation-to-dispersion velocity ratio, V/σ, displays the strongest (anti)-correlation with $f_{M_{*,\mathrm{IHSC}}}$ at fixed M*, tot of all the galaxy and halo properties explored, transitioning from $f_{M_{*,\mathrm{IHSC}}} 0.1$ per cent for high V/σ, to $f_{M_{*,\mathrm{IHSC}}}\approx 5$ per cent for low V/σ galaxies. By studying the $f_{M_{*,\mathrm{IHSC}}}$ temporal evolution, we find that, in the former, mergers not always take place, but if they did, they happened early (z > 1), while the high $f_{M_{*,\mathrm{IHSC}}}$ population displays a much more active merger history. In the case of massive groups and galaxy clusters, $M_{*,\mathrm{tot}}rsim 10^{12}\, \mathrm{M}_\odot$ , a fraction $f_{M_{*,\mathrm{IHSC}}}\approx 10-20$ per cent is reached at z ≍ 1 and then they evolve across lines of constant $f_{M_{*,\mathrm{IHSC}}}$ modulo some small perturbations. Because of the limited simulation's volume, the latter is only tentative and requires a larger sample of simulated galaxy clusters to confirm.
Fichier principal
Vignette du fichier
staa1027.pdf (9.17 Mo) Télécharger le fichier
Origin Publisher files allowed on an open archive

Dates and versions

insu-03748056 , version 1 (28-05-2024)

Identifiers

Cite

Rodrigo Cañas, Claudia del P. Lagos, Pascal J. Elahi, Chris Power, Charlotte Welker, et al.. From stellar haloes to intracluster light: the physics of the Intra-Halo Stellar Component in cosmological hydrodynamical simulations. Monthly Notices of the Royal Astronomical Society, 2020, 494, pp.4314-4333. ⟨10.1093/mnras/staa1027⟩. ⟨insu-03748056⟩
8 View
0 Download

Altmetric

Share

Gmail Mastodon Facebook X LinkedIn More