23–25 oct. 2018
Institut d'Astrophysique de Paris
Fuseau horaire Europe/Paris

The interplay between Dark energy & modified gravity on the amplitude of matter fluctuations discrepancy between CMB and Galaxy Clusters.

Non programmé
15m
Amphithéatre (Institut d'Astrophysique de Paris)

Amphithéatre

Institut d'Astrophysique de Paris

98bis Boulevard Arago, 75014 Paris

Orateur

Dr Ziad SAKR (IRAP - USJ)

Description

In the frame of the dark energy colloquium, we investigate the impact of a dark energy different from fiducial $\Lambda$CDM, on a discrepancy on the amplitude of matter fluctuation $\sigma_8$ found between local and deep probes. In particular between local, X ray, or near universe, SZ detected cluster counts samples and deep CMB temperature and polarization angular correlation spectrums.
We perform our analysis using MCMC techniques, leaving, along with the relevant dark energy and cosmological parameters, the cluster calibration factor free to vary in a model independent approach.
We then confront the dark energy equation of state parameter $w$ to a modified gravity phenomenological parameter, the growth index $\gamma$, in their ability to alleviate the tension. We also show cases were we allow massive neutrinos to vary as well as adding further constraints from other secondary probes like BAO or SNe.

Auteur principal

Dr Ziad SAKR (IRAP - USJ)

Documents de présentation

Aucun document.