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arXiv · 1612.09023

Determining $H_0$ with the latest HII galaxy measurements

Deng Wang·Xin-He Meng
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Abstract

We use the latest HII galaxy measurements to determine the value of $H_0$ adopting a combination of model-dependent and model-independent method. By constraining five cosmological models, we find that the obtained values of $H_0$ are more consistent with the recent local measurement by Riess et al. 2016 (hereafter R16) at $1\sigma$ confidence level, and that these five models prefer a higher best-fit value of $H_0$ than R16's result. To check the correctness of $H_0$ values obtained by model-dependent method, for the first time, we implement the model-independent Gaussian processes (GP) using the HII galaxy measurements. We find that the GP reconstructions also prefer a higher value of $H_0$ than R16's result. Therefore, we conclude that the current HII galaxy measurements support a higher cosmic expansion rate.

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Deng Wang, Xin-He Meng. 2016-12-29. Determining $H_0$ with the latest HII galaxy measurements. https://doi.org/10.3847/1538-4357%2Faa667e

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