We report five measurements of the transverse baryonic acoustic scale, $theta_{BAO}$, 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 ($delta z = 0.01$ and $0.02$) in the interval $ z in [0.565, 0.660] $, which contains a large density of galaxies ($sim 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 $ r_s $. Assuming a time-dependent equation-of-state parameter for the dark energy, we also discuss constraints on the main cosmological parameters from $theta_{BAO}$ and CMB data.
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