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arXiv · 1207.4541

Four New Observational $H(z)$ Data From Luminous Red Galaxies of Sloan Digital Sky Survey Data Release Seven

Cong Zhang·Han Zhang·Shuo Yuan·Siqi Liu·Tong-Jie Zhang·Yan-Chun Sun
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Abstract

By adopting the differential age method, we utilize selected 17832 luminous red galaxies (LRGs) from Sloan Digital Sky Survey Data Release Seven (SDSS DR7) covering redshift $0<z<0.4$ to measure Hubble parameters. Using a full spectrum fitting package UlySS, these spectra are reduced with single stellar population (SSP) models and optimal age information of our selected sample are derived. With the decreasing age-redshift relation, four new observational $H(z)$ data (OHD) points are obtained, which are $H(z)=69.0\pm19.6$ km s$^{-1}$ Mpc$^{-1}$ at $z=0.07$, $H(z)=68.6\pm26.2$ km s$^{-1}$ Mpc$^{-1}$ at $z=0.12$, $H(z)$=$72.9\pm29.6$ km s$^{-1}$ Mpc$^{-1}$ at $z=0.2$ and $H(z)$=$88.8\pm36.6$ km s$^{-1}$ Mpc$^{-1}$ at $z=0.28$, respectively. Combined with other 21 available OHD data points, a performance of constraint on both flat and non-flat $Λ$CDM model is presented.

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Cong Zhang, Han Zhang, Shuo Yuan, Siqi Liu, Tong-Jie Zhang, Yan-Chun Sun. 2014-05-22. Four New Observational $H(z)$ Data From Luminous Red Galaxies of Sloan Digital Sky Survey Data Release Seven. https://doi.org/10.1088/1674--4527%2F14%2F10%2F002

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