Year: 2025
Type: article
Abstract: We investigate the formation history of intrahalo light (IHL) using the high-resolution (∼1 kpc), large-scale (∼1 Gpc) cosmological hydrodynamical simulation Horizon Run 5 (HR5). IHL particles are identified by carefully considering both their binding energies and positions with respect to the tidal radii of individual galaxies. By analyzing more than 1200 galaxy groups and clusters with ≳1013 M ⊙ and tracing their individual IHL particles back in time, we classify the origin of each IHL particle at each epoch, based on the status of the originating galaxy, into one of three categories: brightest halo galaxy (BHG) formation/merger, satellite galaxy stripping, and preprocessing. Our study reveals that IHL production through BHG formation/merger is the predominant production channel, contributing over 60% of the total IHL mass across all redshifts. The second most significant IHL production channel is preprocessing, providing more than 20% in the final HR5 snapshot. Stripping is negligible at z > 4 but becomes gradually more important as the halos mature at z < 4. Finally, we verify that the IHL production through the disruption of dwarf galaxies and in situ formation is negligible, contributing less than ∼3% and ∼0.5% to the total IHL production, respectively.
Source: The Astrophysical Journal
Institutions: Yonsei University, University of California, Davis, Korea Institute for Advanced Study, Korea Astronomy and Space Science Institute, Korea University of Science and Technology, Centre National de la Recherche Scientifique, University of Exeter, Université Paris Sciences et Lettres, Observatoire de Paris, Galaxies, Etoiles, Physique et Instrumentation, Commissariat à l'Énergie Atomique et aux Énergies Alternatives, Institut d'Astrophysique de Paris, Sorbonne Université, Service de Physique de l'État Condensé, Institut de Physique Théorique, University of Hull, Korea Institute of Science & Technology Information
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $4,499
Funders: National Research Foundation, Korea Institute of Science and Technology, Korea Institute of Science and Technology Information, National Research Foundation of Korea, Korea Research Environment Open Network, National Supercomputing Center, Korea Institute of Science and Technology Information
OpenAlex ID: W4413894164