Dark energy parametrizations and their effect on dark halos

Abstract

There are a plethora of dark energy parametrizations that can fit current supernovae Iadata. However, these data are only sensitive to redshifts up to order one. In fact, many ofthese parametrizations break down at higher redshifts. In this paper we study the effect ofdark energy models on the formation of dark halos. We select a couple of dark energyparametrizations which are sensible at high redshifts and compute their effecton the evolution of density perturbations in the linear and non-linear regimes.Using the Press–Schechter formalism we show that they produce distinguishablesignatures in the number counts of dark halos. Therefore, future observations of galaxyclusters can provide complementary constraints on the behaviour of dark energy.