The transverse baryonic acoustic scale from the SDSS DR11 galaxies

Abstract We report five measurements of the transverse baryonic acoustic scale, θBAO, obtained from the angular two-point correlation function calculation for Luminous Red Galaxies of the eleventh data release of the Sloan Digital Sky Survey (SDSS). Each measurement has been obtained by considering a thin redshift shell ( Δ z = 0.01 and 0.02) in the interval z ∈ [0.565, 0.660], which contains a large density of galaxies ( ∼ 20, 000 galaxies/redshift shell). Differently from the three-dimensional Baryon Acoustic Oscillations (BAO) measurements, these data points are obtained almost model-independently and provide a Cosmic Microwave Background (CMB)-independent way to estimate the sound horizon rs. Assuming a time-dependent equation-of-state parameter for the dark energy, we also discuss constraints on the main cosmological parameters from θBAO and CMB data.