Arc Statistics in Cosmological Models with Dark Energy

Preprint
Publisher Website
Google Scholar
  • 2 October 2002
Abstract
We investigate how the probability for the formation of giant arcs in galaxy clusters is expected to change in cosmological models dominated by dark energy with an equation of state p=w rho c^2 compared to cosmological-constant or open models. For doing so, we use a simple analytic model for arc cross sections which we demonstrate to reproduce essential features of numerically determined arc cross sections. Since analytic lens models are known to be inadequate for accurate absolute quantifications of arc probabilities, we use them only for studying changes relative to cosmological-constant models. Our main results are that the order of magnitude difference between the arc probabilities in low density, spatially flat and open CDM models found numerically are reproduced by our analytic model, and that arc statistics can be reconciled with spatially flat cosmological models with low matter density if the dark energy equation of state w is larger than -1.

This publication has 0 references indexed in Scilit: