English

The integrated Sachs-Wolfe effect in cosmologies with coupled dark matter and dark energy

Astrophysics 2013-03-07 v1

Abstract

The subject of this paper is the derivation of the integrated Sachs-Wolfe (iSW) effect in cosmologies with coupled dark matter and dark energy fluids. These couplings influence the iSW-effect in three ways: The Hubble function assumes a different scaling, the structure growth rate shows a different time evolution, and in addition, the Poisson equation, which relates the density perturbations to fluctuations in the gravitational potential, is changed, due to the violation of the scaling rho ~ a^{-3} of the matter density rho with scale factor a. Exemplarily, I derive the iSW-spectra for a model in which dark matter decays into dark energy, investigate the influence of the dark matter decay rate and the dark energy equation of state on the iSW-signal, and discuss the analogies for gravitational lensing. Quite generally iSW-measurements should reach similar accuracy in determining the dark energy equation of state parameter and the coupling constant.

Keywords

Cite

@article{arxiv.0803.2239,
  title  = {The integrated Sachs-Wolfe effect in cosmologies with coupled dark matter and dark energy},
  author = {Bjoern Malte Schaefer},
  journal= {arXiv preprint arXiv:0803.2239},
  year   = {2013}
}

Comments

5 pages, 4 figures, 1 table, submitted to MNRAS