skip to main content

SciTech ConnectSciTech Connect

Title: Mergers and mass accretion for infalling halos both end well outside cluster virial radii

We find that infalling dark matter halos (i.e., the progenitors of satellite halos) begin losing mass well outside the virial radius of their eventual host halos. The peak mass occurs at a range of clustercentric distances, with median and 68th percentile range of 1.8{sub −1.0}{sup +2.3} R{sub vir,host} for progenitors of z = 0 satellites. The peak circular velocity for infalling halos occurs at significantly larger distances (3.7{sub −2.2}{sup +3.3} R{sub vir,host} at z = 0). This difference arises because different physical processes set peak circular velocity (typically, ∼1:5 and larger mergers which cause transient circular velocity spikes) and peak mass (typically, smooth accretion) for infalling halos. We find that infalling halos also stop having significant mergers well before they enter the virial radius of their eventual hosts. Mergers larger than a 1:40 ratio in halo mass end for infalling halos at similar clustercentric distances (∼1.9 R {sub vir,} {sub host}) as the end of overall mass accretion. However, mergers larger than 1:3 typically end for infalling halos at more than four virial radial away from their eventual hosts. This limits the ability of mergers to affect quenching and morphology changes in clusters. We also note that the transient spikesmore » which set peak circular velocity may lead to issues with abundance matching on that parameter, including unphysical galaxy stellar mass growth profiles near clusters; we propose a simple observational test to check if a better halo proxy for galaxy stellar mass exists.« less
Authors:
 [1] ; ; ;  [2] ;  [3] ;  [4] ;  [5]
  1. Space Telescope Science Institute, Baltimore, MD 21218 (United States)
  2. Physics Department, Stanford University, Department of Particle and Particle Astrophysics, SLAC National Accelerator Laboratory, Kavli Institute for Particle Astrophysics and Cosmology Stanford, CA 94305 (United States)
  3. Institute for Astronomy, ETH Zurich, 8093-CH Zurich (Switzerland)
  4. Astronomy Department, New Mexico State University, Las Cruces, NM 88003 (United States)
  5. Department of Physics, University of California at Santa Cruz, Santa Cruz, CA 95064 (United States)
Publication Date:
OSTI Identifier:
22356749
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 787; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ABUNDANCE; DISTANCE; EVOLUTION; GALAXIES; GROWTH; MASS; NONLUMINOUS MATTER; SATELLITES; TRANSIENTS; VELOCITY