Cosmological Measurements from Angular Power Spectra Analysis of BOSS DR12 Tomography

Abstract

We constrain cosmological parameters by analysing the angular power spectra of the Baryon Oscillation Spectroscopic Survey DR12 galaxies, a spectroscopic follow-up of around 1.3 million SDSS galaxies over 9,376 deg${}^2$ with an effective volume of $\sim 6.5$ (Gpc $h^{-1}$)${}^3$ in the redshift range $0.15\le z<0.80$. We split this sample into 13 tomographic bins ($\hat{I}”z=0.05$); angular power spectra were calculated using a Pseudo-$C_{\ell }$ estimator, and covariance matrices were estimated using log-normal simulated maps. Cosmological constraints obtained from these data were combined with constraints from Planck CMB experiment as well as the JLA supernovae compilation. Considering a $w$CDM cosmological model measured on scales up to $k_{max}=0.07h$ Mpc${}^{-1}$, we constrain a constant dark energy equation-of-state with a $\sim 4\%$ error at the 1-$\ddot{I}ƒ$ level: $w_0=-0.993_{-0.043}^{+0.046}$, together with $\hat{I}{\text{c◯}}_m=0.330\pm 0.012$, $\hat{I}{\text{c◯}}_b=0.0505\pm 0.002$, $S_8\equiv \ddot{I}{ƒ}_8\sqrt{\hat{I}{\text{c◯}}_m/0.3}=0.863\pm 0.016$, and $h=0.661\pm 0.012$. For the same combination of datasets, but now considering a $\hat{I}›$CDM model with massive neutrinos and the same scale cut, we find: $\hat{I}{\text{c◯}}_m=0.328\pm 0.009$, $\hat{I}{\text{c◯}}_b=0.05017_{-0.0008}^{+0.0009}$, $S_8=0.862\pm 0.017$, and $h=0.663_{-0.007}^{+0.006}$ and a 95\% credible interval (CI) upper limit of $\sum m_{\hat{I}}½<0.14$ eV for a normal hierarchy. These results are competitive if not better than standard analyses with the same dataset, and demonstrate this should be a method of choice for future surveys, opening the door for their full exploitation in cross-correlations probes.

28 pages, 28 figures, 3 appendices