Peculiar velocities of rich clusters in hot and cold dark matter models

Abstract

view Abstract Citations (2) References (26) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS Peculiar Velocities of Rich Clusters in Hot and Cold Dark Matter Models Rhee, George Abstract We examine the peculiar velocities of rich clusters of galaxies in numerical simulations of hot (HDM) and cold dark matter (CDM) universes. We have identified rich clusters in these simulations using a friends of friends algorithm and studied the amplitude and evolution of cluster peculiar velocities with time, The mean cluster peculiar velocity in a CDM universe is 313 km s^-1^ for a bias factor of 2.5, increasing to 614 km s^-1^ for a bias factor of 1.0. For an HDM universe these values are 289 km s^-1^ for b = 2.5 and 661 km s^-1^ for b = 1. The cluster peculiar motion amplitudes determined from the simulations are in conflict with recent observational claims of cluster peculiar motions as large as ~2000 km s^-1^. We find that the growth rate of cluster peculiar motions ν_p_ is proportional to a is larger than that predicted by linear theory ν_p_ is proportional to a^1/2^. We have examined the agreement between the force and peculiar velocity vectors in these simulations to see if one might derive the large-scale density field from cluster peculiar velocities. Our analysis indicates that this may be done for low bias parameters b < 1.5 in both the hot and cold dark matter galaxy formation scenarios. Publication: The Astrophysical Journal Pub Date: July 1993 DOI: 10.1086/172848 Bibcode: 1993ApJ...411..455R Keywords: Astrometry; Astronomical Models; Dark Matter; Galactic Clusters; Galactic Evolution; Red Shift; Cosmology; Digital Simulation; Many Body Problem; Velocity Distribution; Astrophysics; COSMOLOGY: DARK MATTER; GALAXIES: CLUSTERING; GALAXIES: DISTANCES AND REDSHIFTS full text sources ADS | data products SIMBAD (2)