Dynamical Dark Energy model parameters with or without massive neutrinos

TL;DR

This study constrains parameters of quintessence dark energy models using WMAP5 data, examining the impact of neutrino masses on these constraints and identifying shifts in best-fit parameters.

Contribution

It provides updated constraints on quintessence model parameters with WMAP5 data, analyzing the effects of including neutrino masses on these constraints and parameter shifts.

Findings

Upper limits on energy scale mbda are very small (~10^{-9} to 10^{-5})

Constraints on mbda are not significantly affected by neutrino mass inclusion

Allowing neutrino mass causes notable shifts in other model parameters

Abstract

We use WMAP5 and other cosmological data to constrain model parameters in quintessence cosmologies, focusing also on their shift when we allow for non-vanishing neutrino masses. The Ratra-Peebles (RP) and SUGRA potentials are used here, as examples of slowly or fastly varying state parameter w(a). Both potentials depend on an energy scale \Lambda. Here we confirm the results of previous analysis with WMAP3 data on the upper limits on \Lambda, which turn out to be rather small (down to ~10^{-9} in RP cosmologies and ~10^{-5} for SUGRA). Our constraints on \Lambda are not heavily affected by the inclusion of neutrino mass as a free parameter. On the contrary, when the neutrino mass degree of freedom is opened, significant shifts in the best-fit values of other parameters occur.