2015/01/14 by Yang Wang, Weipeng Lin, F. R. Pearce +5
Physics and Astronomy · #Angular momentum #Astrophysics #Classical mechanics #Condensed matter physics #Cosmology and Gravitation Theories #Galaxies: Formation, Evolution, Phenomena #Galaxy #Halo #Physics #Population #Redshift #Scientific Research and Discoveries #Spin (aerodynamics) #Spins #astro-ph.GA
paper · pdf · doi:10.1088/0004-637x/801/2/93
published as Yang Wang et al. 2015 ApJ 801 93 · 10 pages; 5 figures
arxiv created 2015/01/14 · openalex publication_date 2015/03/10 · arxiv updated 2015/03/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Investigating the spin parameter distribution of subhalos in two high-resolution isolated halo simulations, recent work by Onions et al. suggested that typical subhalo spins are consistently lower than the spin distribution found for field halos. To further examine this puzzle, we have analyzed simulations of a cosmological volume with sufficient resolution to resolve a significant subhalo population. We confirm the result of Onions et al. and show that the typical spin of a subhalo decreases with decreasing mass and increasing proximity to the host halo center. We interpret this as the growing influence of tidal stripping in removing the outer layers, and hence the higher angular momentum particles, of the subhalos as they move within the host potential. Investigating the redshift dependence of this effect, we find that the typical subhalo spin is smaller with decreasing redshift. This indicates a temporal evolution, as expected in the tidal stripping scenario.