# Are Cold Dynamical Dark Energy Models Distinguishable in the Light of the Data? [CEA]

In this paper we obtain observational constraints on three dynamical cold dark energy models ,include PL , CPL and FSL, with most recent cosmological data and investigate their implication for structure formation, dark energy clustering and abundance of CMB local peaks. From the joint analysis of the CMB temperature power spectrum from observation of the Planck, SNIa light-curve, baryon acoustic oscillation, $f\sigma_8$ for large scale structure observations and the Hubble parameter, the PL model has the highest growth of matter density, $\Delta_{m}$, and matter power spectrum, $P(k)$, compared to $\Lambda$CDM and other models. For the CPL on the other hand, the structure formation is considerably suppressed while the FSL has behavior similar to standard model of cosmology. Studying the clustering of dark energy, $\Delta_{DE}$, yields positive but small value with maximum of $\Delta_{DE}\simeq10^{-3}$ at early time due to matter behaviour of the PL, while for the CPL and FSL cross $\Delta_{DE}=0$ several time which demonstrate void of dark energy with $\Delta_{DE}\simeq-10^{-11}$ in certain periods of the history of dark energy evolution. Among these three models, the PL model demonstrate that is more compatible with $f\sigma_{8}$ data. We also investigated a certain geometrical measure, namely the abundance of local maxima as a function of threshold for three DDE models and find that the method is potentially capable to discriminate between the models, especially far from mean threshold. The contribution of PL and CPL for late ISW are significant compared to cosmological constant and FSL model. The tension in the Hubble parameters is almost alleviated in the PL model.

A. Ebrahimi, M. Monemzadeh and H. Moshafi
Thu, 15 Feb 18
4/48