Measuring $H_0$ from low-$z$ datasets

Xue Zhang; Qing-Guo Huang

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arXiv · 1911.09439

Measuring $H_0$ from low-$z$ datasets

Xue Zhang·Qing-Guo Huang

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Abstract

Adopting the low-redshift observational datasets, including the Pantheon sample of Type Ia supernovae, baryon acoustic oscillation measurements, and the tomographic Alcock-Paczynski method, we determine the Hubble constant to be $67.95^{+0.78}_{-1.03}$ , $69.81^{+2.22}_{-2.70}$ and $66.75^{+3.42}_{-4.23}$ km s$^{-1}$ Mpc$^{-1}$ at 68\% confidence level in the $\Lambda$CDM, $w$CDM and $w_0w_a$CDM models, respectively. Compared to the Hubble constant given by Riess et al. in 2019, we conclude that the new physics beyond the standard $\Lambda$CDM model is needed if all of these datasets are reliable.

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Xue Zhang, Qing-Guo Huang. 2019-11-21. Measuring $H_0$ from low-$z$ datasets. https://arxiv.org/abs/1911.09439

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