Cosmological constrains from X-ray AGN clustering and SNIa data

We put constraints on the main cosmological parameters of different spatially flat cosmological models by combining the recent clustering results of XMM-Newton soft (0.5-2 keV) X-ray sources, which have a redshift distribution with median redshift $z\sim 1.2$, and SNIa data. Using a likelihood procedure we find that the model which best reproduces the observational data and that is consistent with stellar ages is the concordance $\mathrm{\Lambda }$CDM model with: ${\mathrm{\Omega }}_{\mathrm{m}}\simeq 0.28$, $w\simeq -1$, $H_{\circ }\simeq 72$ km s${}^{-1}$ Mpc${}^{-1}$, $t_{\circ }\simeq 13.5$Gyr and has an X-ray AGN clustering evolution which is constant in physical coordinates. For a different clustering evolution model (constant in comoving coordinates) we find another viable model, although less probable due to the smaller age of the Universe, with $\Omega_{\rm m}\simeq 0.38$,$w\simeq -1.25$,$H_{\circ} \simeq 70$kms$^{-1}$Mpc$^{-1}$,$t_{\circ}\simeq 12.9$Gyr.