Observational constraints on an interacting dark energy model

Details Observational constraints on an interacting dark energy model Observational constraints on an interacting dark energy model

2009-07-29

arxiv.org/abs/0907.4987v2

Mon. Not. R. Astron. Soc. 402, 2355-2368 (2010)

Astronomy and Astrophysics

Astrophysics

Cosmology and Extragalactic Astrophysics

16 pages, 10 figures. V2: Improved typography (2-column format); References and a motivation of CPL parametrization added; Acc

Scientific paper

10.1111/j.1365-2966.2009.16115.x

We use observations of cosmic microwave background anisotropies, supernova luminosities and the baryon acoustic oscillation signal in the galaxy distribution to constrain the cosmological parameters in a simple interacting dark energy model with a time-varying equation of state. Using a Monte Carlo Markov Chain technique we determine the posterior likelihoods. Constraints from the individual data sets are weak, but the combination of the three data sets confines the interaction constant $\Gamma$ to be less than 23% of the expansion rate of the Universe $H_0$; at 95% CL $-0.23 < \Gamma/H_0 < +0.15$. The CMB acoustic peaks can be well fitted even if the interaction rate is much larger, but this requires a larger or smaller (depending on the sign of interaction) matter density today than in the non-interacting model. Due to this degeneracy between the matter density and the interaction rate, the only observable effect on the CMB is a larger or smaller integrated Sachs-Wolfe (ISW) effect. While SN or BAO data alone do not set any direct constraints on the interaction, they exclude the models with very large matter density, and hence indirectly constrain the interaction rate when jointly analysed with the CMB data. To enable the analysis described in this paper, we present in a companion paper [arXiv:0907.4981] a new systematic analysis of the early radiation era solution to find the adiabatic initial conditions for the Boltzmann integration.

Affiliated with

Also associated with

No associations

Rating

Observational constraints on an interacting dark energy model does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Observational constraints on an interacting dark energy model, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Observational constraints on an interacting dark energy model will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-520869