Shear and vorticity in the spherical collapse of dark matter haloes

Abstract

Traditionally the spherical collapse of objects is studied with respect to a uniform background density, yielding the critical over-density ${\delta }_{\mathrm{c}}$ as key ingredient to the mass function of virialized objects. Here we investigate the shear and rotation acting on a peak in a Gaussian random field. By assuming that collapsing objects mainly form at those peaks, we use this shear and rotation as external effects changing the dynamics of the spherical collapse, which is described by the Raychaudhuri equation. We therefore assume that the shear and rotation have no additional dynamics on top of their cosmological evolution and thus only appear as inhomogeneities in the differential equation.

8 pages, 5 figures, MNRAS accepted

References in corpus (6)

• Dynamics of dark energy
• Effects of shear and rotation on the spherical collapse model for clustering dark energy
• The signature of dark energy perturbations in galaxy cluster surveys
• Constraining Dark Energy by Combining Cluster Counts and Shear-Shear Correlations in a Weak Lensing Survey
• Spherical collapse of dark matter haloes in tidal gravitational fields
• Effects of tidal gravitational fields in clustering dark energy models

Cited by in corpus (7)

• The Hunt for Primordial Interactions in the Large Scale Structures of the Universe
• A high precision semi-analytic mass function
• Halo collapse: virialization by shear and rotation in dynamical dark-energy models. Effects on weak-lensing peaks
• Quasi-spherical collapse of matter in $\Lambda$CDM
• Effects of Rastall parameter on perturbation of dark sectors of the Universe
• Tidal virialization of dark matter haloes with clustering dark energy
• Effects of dynamical friction on perturbations for evolving dark energy