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arXiv · 1506.08274

Cosmological implications of different baryon acoustic oscillation data

Abstract

In this work, we explore the cosmological implications of different baryon acoustic oscillation (BAO) data, including the BAO data extracted by using the spherically averaged one-dimensional galaxy clustering (GC) statistics (hereafter BAO1) and the BAO data obtained by using the anisotropic two-dimensional GC statistics (hereafter BAO2). To make a comparison, we also take into account the case without BAO data (hereafter NO BAO). Firstly, making use of these BAO data, as well as the SNLS3 type Ia supernovae sample and the Planck distance priors data, we give the cosmological constraints of the $\Lambda$CDM, the $w$CDM, and the Chevallier-Polarski-Linder (CPL) model. Then, we discuss the impacts of different BAO data on cosmological consquences, including its effects on parameter space, equation of state (EoS), figure of merit (FoM), deceleration-acceleration transition redshift, Hubble parameter $H(z)$, deceleration parameter $q(z)$, statefinder hierarchy $S^{(1)}_3(z)$, $S^{(1)}_4(z)$ and cosmic age $t(z)$. We find that: (1) NO BAO data always give a smallest fractional matter density $\Omega_{m0}$, a largest fractional curvature density $\Omega_{k0}$ and a largest Hubble constant $h$; in contrast, BAO1 data always give a largest $\Omega_{m0}$, a smallest $\Omega_{k0}$ and a smallest $h$. (2) For the $w$CDM and the CPL model, NO BAO data always give a largest EoS $w$; in contrast, BAO2 data always give a smallest $w$. (3) Compared with the case of BAO1, BAO2 data always give a slightly larger FoM, and thus can give a cosmological constraint with a slightly better accuracy. (4) The impacts of different BAO data on the cosmic evolution and the comic age are very small, and can not be distinguished by using various dark energy diagnosis and the cosmic age data.

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Shuang Wang, Yazhou Hu, Miao Li. 2015-06-27. Cosmological implications of different baryon acoustic oscillation data. https://doi.org/10.1007/s11433-016-0486-6

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