Antonino Del Popolo

Effects of shear and rotation on the spherical collapse model for clustering dark energy

In the framework of the spherical collapse model we study the influence of shear and rotation terms for dark matter fluid in clustering dark energy models. We evaluate, for different equations of state, the effects of these terms on the linear overdensity threshold parameter,

Small Scale Problems of the

delta_{rm c}

\Lambda

, and on the virial overdensity,

CDM Model: A Short Review

Delta_{rm V}

Constraints on shear and rotation with massive galaxy clusters

. The evaluation of their effects on

Evidence against cuspy dark matter haloes in large galaxies

delta_{rm c}

A high precision semi-analytic mass function

allows us to infer the modifications occurring on the mass function. Due to ambiguities in the definition of the halo mass in the case of clustering dark energy, we consider two different situations: the first is the classical one where the mass is of the dark matter halo only, while the second one is given by the sum of the mass of dark matter and dark energy. As previously found, the spherical collapse model becomes mass dependant and the two additional terms oppose to the collapse of the perturbations, especially on galactic scales, with respect to the spherical non-rotating model, while on clusters scales the effects of shear and rotation become negligible. The values for

Absence of a fundamental acceleration scale in galaxies

delta_{rm c}

Quantifying Departures from Equilibrium with the Spherical Jeans Equation

and

On the first crossing distributions in fractional Brownian motion and the mass function of dark matter haloes

Delta_{rm V}