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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 $0.15 leq z < 0.80$. We split this sample into 13 tomographic bins ($Delta z = 0.05$); 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-$sigma$ level: $w_0 = -0.993^{+0.046}_{-0.043}$, together with $Omega_m = 0.330pm 0.012$, $Omega_b = 0.0505 pm 0.002$, $S_8 equiv sigma_8 sqrt{Omega_m/0.3} = 0.863 pm 0.016$, and $h = 0.661 pm 0.012$. For the same combination of datasets, but now considering a $Lambda$CDM model with massive neutrinos and the same scale cut, we find: $Omega_m = 0.328 pm 0.009$, $Omega_b = 0.05017^{+0.0009}_{-0.0008}$, $S_8 = 0.862 pm 0.017$, and $h = 0.663^{+0.006}_{-0.007}$ and a 95% credible interval (CI) upper limit of $sum m_{ u} < 0.14$ 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.
We make use of recent developments in the analysis of galaxy redshift surveys to present an easy to use matrix-based analysis framework for the galaxy power spectrum multipoles, including wide-angle effects and the survey window function. We employ t
Our observations of the Universe are fundamentally anisotropic, with data from galaxies separated transverse to the line of sight coming from the same epoch while that from galaxies separated parallel to the line of sight coming from different times.
We present a cosmic void catalog using the large-scale structure galaxy catalog from the Baryon Oscillation Spectroscopic Survey (BOSS). This galaxy catalog is part of the Sloan Digital Sky Survey (SDSS) Data Release 12 and is the final catalog of SD
In this study, we probe the transition to cosmic homogeneity in the Large Scale Structure (LSS) of the Universe using the CMASS galaxy sample of BOSS spectroscopic survey which covers the largest effective volume to date, $3 h^{-3} mathrm{Gpc}^3$ at
Future galaxy clustering surveys will probe small scales where non-linearities become important. Since the number of modes accessible on intermediate to small scales is very high, having a precise model at these scales is important especially in the