Reconstruction of interaction rate in Holographic dark energy

TL;DR

This paper reconstructs the interaction rate between dark energy and dark matter in a holographic dark energy model using multiple observational data sets, finding a consistently positive and increasing interaction rate.

Contribution

It introduces a reconstruction of the interaction rate for three parameterizations of the deceleration parameter using extensive observational data, providing tighter constraints than previous studies.

Findings

Interaction rate remains positive and increases with expansion.

Tighter constraints on the interaction rate due to larger data sets.

Models are statistically close in terms of Bayesian evidence.

Abstract

The present work is based on the holographic dark energy model with Hubble horizon as the infrared cut-off. The interaction rate between dark energy and dark matter has been reconstructed for three different parameterizations of the deceleration parameter. Observational constraints on the model parameters have been obtained by maximum likelihood analysis using the observational Hubble parameter data (OHD), type Ia supernovab data (SNe), baryon acoustic oscillation data (BAO) and the distance prior of cosmic microwave background (CMB) namely the CMB shift parameter data (CMBShift). The interaction rate obtained in the present work remains always positive and increases with expansion. It is very similar to the result obtained in previous findings where the interaction rate has been reconstructed for a parametrization of the dark energy equation of state. Tighter constraints on the interaction rate have been obtained in the present work as it is based on larger data sets. The nature of the dark energy equation of state parameter has also been studied for the present models. Though the reconstruction is done from different parametrizations, the overall nature of the interaction rate is very similar in all the cases. Different information criteria and the Bayesian evidence, which have been invoked in the context of model selection, show that the these models are at close proximity of each other.