On the spin distributions of $\Lambda$CDM haloes

Abstract

We used merger trees realizations, predicted by the extended Press-Schechter theory, in order to study the growth of angular momentum of dark matter haloes. Our results showed that: 1) The spin parameter ${\lambda }^{\prime }$ resulting from the above method, is an increasing function of the present day mass of the halo. The mean value of ${\lambda }^{\prime }$ varies from 0.0343 to 0.0484 for haloes with present day masses in the range of $10^9{\mathrm{h}}^{-1}{M}_{\odot }$ to $10^{14}{\mathrm{h}}^{-1}{M}_{\odot }$. 2)The distribution of ${\lambda }^{\prime }$ is close to a log-normal, but, as it is already found in the results of N-body simulations, the match is not satisfactory at the tails of the distribution. A new analytical formula that approximates the results much more satisfactorily is presented. 3) The distribution of the values of ${\lambda }^{\prime }$ depends only weakly on the redshift. 4) The spin parameter of an halo depends on the number of recent major mergers. Specifically the spin parameter is an increasing function of this number.

10 pages, 8 figures

References in corpus (9)

• Simulating the joint evolution of quasars, galaxies and their large-scale distribution
• Concentration, Spin and Shape of Dark Matter Haloes: Scatter and the Dependence on Mass and Environment
• Internal and External Alignment of the Shapes and Angular Momenta of LCDM Halos
• Shapes and Alignments of Galaxy Cluster Halos
• The dependence on environment of Cold Dark Matter Halo properties
• On Random Walks with a General Moving Barrier
• Mass Function of Low Mass Dark Halos
• Formation time distribution of dark matter haloes: theories versus N-body simulations
• On the reliability of merger-trees and the mass growth histories of dark matter haloes

Cited by in corpus (2)

• Dissecting the spin distribution of Dark Matter halos
• Quantifying galactic morphological transformations in the cluster environment