Dynamical and observational analysis of interacting models

TL;DR

This paper studies a class of dark sector interaction models where dark matter and dark energy are coupled via a power law of the scale factor, showing dark energy dominance and constraining parameters with observational data.

Contribution

It introduces a new class of interacting dark sector models with a power law coupling and provides observational constraints on their parameters.

Findings

Dark energy dominates current cosmic composition.

The model can alleviate the coincidence problem.

Constraints on model parameters from observational data.

Abstract

We investigate the dynamical behaviour of a general class of interacting models in the dark sector in which the phenomenological coupling between cold dark matter and dark energy is a power law of the cosmic scale factor. From numerical simulations we show that, in this background, dark energy always dominates the current composition cosmic. This behaviour may alleviate substantially the coincidence problem. By using current type Ia supernovae, baryonic acoustic oscillations and cosmic microwave background data, we perform a joint statistical analysis and obtain constraints on free parameters of this class of model.