Kushal T. Mehta, Antonio J. Cuesta, Xiaoying Xu, Daniel J. Eisenstein, Nikhil Padmanabhan
We use the 2% distance measurement from our reconstructed baryon acoustic
oscillations (BAOs) signature using the Sloan Digital Sky Survey (SDSS) Data
Release 7 (DR7) Luminous Red Galaxies (LRGs) from Padmanabhan et al. (2012) and
Xu et al. (2012) combined with cosmic microwave background (CMB) data from
Wilkinson Microwave Anisotropy Probe (WMAP7) to measure parameters for various
cosmological models. We find a 1.7% measurement of H_0 = 69.8 +/- 1.2 km/s/Mpc
and a 5.0% measurement of \Omega_m = 0.280 +/- 0.014 for a flat Universe with a
cosmological constant. These measurements of H_0 and Omega_m are robust against
a range of underlying models for the expansion history. We measure the dark
energy equation of state parameter w = -0.92 +/- 0.13, which is consistent with
a cosmological constant. If curvature is allowed to vary, we find that the
Universe is consistent with a flat geometry (\Omega_K = -0.004 +/- 0.005). We
also use a combination of the 6 Degree Field Galaxy Survey BAO data, WiggleZ
Dark Energy Survey data, Type Ia supernovae (SN) data, and a local measurement
of the Hubble constant to explore cosmological models with more parameters.
Finally, we explore the effect of varying the energy density of relativistic
particles on the measurement of H_0.
View original:
http://arxiv.org/abs/1202.0092
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