Date Published:
October 1, 2013
Abstract:
We analyse the 2D correlation function of the Sloan Digital SkySurvey-III Baryon Oscillation Spectroscopic Survey (BOSS) CMASS sampleof massive galaxies of the ninth data release to measure cosmicexpansion H and the angular diameter distance D
A at a meanredshift of = 0.57. We apply, for the first time, a newcorrelation function technique called clustering wedgesξ
Δμ(s). Using a physically motivated model, theanisotropic baryonic acoustic feature in the galaxy sample is detectedat a significance level of 4.7σ compared to a featureless model.The baryonic acoustic feature is used to obtain model-independentconstraints cz/H/r
s = 12.28 ± 0.82 (6.7 percentaccuracy) and D
A/r
s = 9.05 ± 0.27 (3.0 percent) with a correlation coefficient of -0.5, where r
s is thesound horizon scale at the end of the baryonic drag era. We conductthorough tests on the data and 600 simulated realizations, findingrobustness of the results regardless of the details of the analysismethod. Combining this with r
s constraints from the cosmicmicrowave background, we obtain H(0.57) = 90.8 ± 6.2 kms
-1 Mpc
-1 and D
A(0.57) = 1386 ±45 Mpc. We use simulations to forecast results of the final BOSS CMASSdata set. We apply the reconstruction technique on the simulationsdemonstrating that the sharpening of the anisotropic baryonic acousticfeature should improve the detection as well as tighten constraints of Hand D
A by ˜30 per cent on average.
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