http://arxiv.org/abs/1905.09689
Model-independent estimates of cosmological quantities are a challenge for observational cosmology. In this paper, we discuss a model-independent way to obtain the present dark matter density parameter ($\Omega_{\rm{c,0}}$) by combining gas mass fraction measurements in galaxy clusters ($f_{gas}$), type Ia supernovae (SNe Ia) observations and measurements of the cosmic baryon abundance from observations of absorption systems at high redshifts. Our estimate is $\Omega_{\rm{c,0}} = 0.241 \pm 0.012$ ($1\sigma$). By considering the latest local measurement of the Hubble constant, $H_0 = 74.03 \pm 1.42$ (1$\sigma$), we obtain $\Omega_{\rm{M,0}} = 0.282 \pm 0.012$ ($1\sigma$) for the total matter density parameter. We also investigate departures of the evolution of the dark matter density with respect to the usual $a^{-3}$ scaling, as usual in interacting models of dark matter and dark energy. As the current data cannot confirm or rule out such an interaction, we perform a forecast analysis to estimate the necessary improvements in number and accuracy of upcoming $f_{gas}$ and SNe Ia observations to detect a possible non-minimal coupling in the cosmological dark sector.
R. Holanda, R. Gonçalves, J. Gonzales, et. al.
Fri, 24 May 19
59/60
Comments: 7 pages, 4 figures