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Raquel Emy Fazolo

Publications and source records attributed to Raquel Emy Fazolo.

3 recordsLinked to original sources

Skewness as a test of dark energy perturbations

We investigate the role played by dark energy perturbations in the skewness $S_3$ of large-scale matter distribution. We consider a two-fluid universe composed by matter and dark energy, with perturbations in both components, and we estimate numerically the skewness of the matter density field as a function of the dark energy parameters. We characterize today's $S_3$ value for quintessence and phantom dark energy cosmologies as well as its dependence on the matter density parameter $Ω_{m0}$ and the dark energy sound speed $c^2_s$ with accurate numerical fitting. These fits can be used to test cosmology against future high quality data on large scale structure.

astro-ph.CO↗

Skewness of matter distribution in clustering dark energy cosmologies

We calculate the skewness (the third moment $S_3$) of matter distribution in dynamical dark energy cosmologies. We pay particular attention to the impact of dark energy perturbations on this quantity. There is indeed a clear signature of dark energy perturbations on this quantity. By properly allowing dark energy perturbations we show that their impact on $S_3$ is strong enough (a factor $\sim 3$ greater) to easily discriminate between clustering and non-clustering dark energy cosmologies. This indicates that high order statistics of the cosmic density field are useful to the study of dark energy models and are potentially able to rule out clustering dark energy cosmologies.

astro-ph.CO↗

Degeneracy between nonadiabatic dark energy models and $Λ$CDM: ISW effect and the cross correlation of CMB with galaxy clustering data

As recently pointed out in Ref. [Phys.\ Rev.\ D {\bf 96}, 8, 083502 (2017)] the evolution of the linear matter perturbations in nonadiabatic dynamical dark energy models is almost indistinguishable (quasi-degenerated) to the standard $Λ$CDM scenario. In this work we extend this analysis to CMB observables in particular the integrated Sachs-Wolfe effect and its cross-correlation with large scale structure. We find that this feature persists for such CMB related observable reinforcing that new probes and analysis are necessary to reveal the nonadiabatic features in the dark energy sector.

astro-ph.CO↗