Measuring baryon acoustic oscillations with angular two-point correlation function

Abstract

The Baryon Acoustic Oscillations (BAO) imprinted a characteristic correlation length in the large-scale structure of the universe that can be used as a standard ruler for mapping out the cosmic expansion history. Here, we discuss the application of the angular two-point correlation function, $w(\hat{I}¸)$, to a sample of luminous red galaxies of the Sloan Digital Sky Survey (SDSS) and derive two new measurements of the BAO angular scale at $z=0.235$ and $z=0.365$. Since noise and systematics may hinder the identification of the BAO signature in the $w-\hat{I}¸$ plane, we also introduce a potential new method to localize the acoustic bump in a model-independent way. We use these new measurements along with previous data to constrain cosmological parameters of dark energy models and to derive a new estimate of the acoustic scale $r_s$.

9 pages, 5 figures. To appear in the Festschrift in honour of Prof. T. Padmanabhan on the occasion of his 60th birthday