Galaxies and their dark-matter haloes have posed several challenges to the dark energy
plus cold dark matter (Λ CDM) cosmological model. These discrepancies between …

Compact objects occupy a pivotal role in the exploration of Nature. The interest spans from
the role of compact objects in astrophysics to their detection through various methods …

This paper introduces C olossus, a public, open-source python package for calculations
related to cosmology, the large-scale structure (LSS) of matter in the universe, and the …

The relation between halo mass, M, and concentration, c, is a critical component in our
understanding of the structure of dark matter halos. While numerous models for this relation …

Formation of galaxy clusters corresponds to the collapse of the largest gravitationally bound
overdensities in the initial density field and is accompanied by the most energetic …

High resolution N-body simulations show that the density profiles of dark matter halos
formed in the standard CDM cosmogony can be fit accurately by scaling a simple “universal” …

We use high-resolution N-body simulations to study the equilibrium density profiles of dark
matter halos in hierarchically clustering universes. We find that all such profiles have the …

We present a numerical study of dark matter halo concentrations in ΛCDM and self-similar
cosmologies. We show that the relation between concentration, c, and peak height, ν …

We present a systematic study of the density profiles of ΛCDM halos, focusing on the outer
regions, 0.1< r/R vir< 9. We show that the median and mean profiles of halo samples of a …

We compare the results of Eulerian hydrodynamic simulations of cluster formation against
virial scaling relations between four bulk quantities: the cluster mass, the dark matter velocity …