Constraining dark energy using observational growth rate data

TL;DR

This paper uses observational growth rate data from galaxy surveys, combined with supernova, BAO, and CMB data, to constrain dark energy models, confirming the consistency of ΛCDM while allowing for time-varying dark energy.

Contribution

It demonstrates the utility of growth rate data in constraining dark energy parameters and highlights its potential with future more accurate data.

Findings

Growth rate data improves dark energy constraints.

ΛCDM model remains consistent with observations.

Future data will enhance dark energy understanding.

Abstract

Observational growth rate data had been derived from observations of redshift distortions in galaxy redshift surveys. Here we use the growth rate data to place constraints on the dark energy model parameters. By performing a joint analysis with the Type Ia supernova, baryon acoustic oscillation and cosmic microwave background data, it is found that the growth rate data are useful for improving the constraints. The joint constraints show that the $\Lambda$CDM model is still in good agreement with current observations, although a time-variant dark energy still cannot be ruled out. It is argued that the growth rate data are helpful for understanding the dark energy. With more accurate data available in the future, we will have a powerful tool for constraining the cosmological and dark energy parameters.