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arXiv · 1106.4294

Hubble parameter data constraints on dark energy

Yun Chen·Bharat Ratra
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Abstract

We use Hubble parameter versus redshift data from Stern, et al(2010) and Gazta\~{n}aga, et al (2009) to place constraints on model parameters of constant and time-evolving dark energy cosmological models. These constraints are consistent with (through not as restrictive as) those derived from supernova Type Ia magnitude-redshift data. However, they are more restrictive than those derived from galaxy cluster angular diameter distance, and comparable with those from gamma-ray burst and lookback time data. A joint analysis of the Hubble parameter data with more restrictive baryon acoustic oscillation peak length scale and supernova Type Ia apparent magnitude data favors a spatially-flat cosmological model currently dominated by a time-independent cosmological constant but does not exclude time-varying dark energy.

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Yun Chen, Bharat Ratra. 2011-06-21. Hubble parameter data constraints on dark energy. https://doi.org/10.1016/j.physletb.2011.08.035

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