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arXiv · 2601.07345

New $H(z)$ measurement at Redshift = 0.12 with DESI Data Release 1

Ze-fan Wang·Lei Lei·Yi-zhong Fan
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Abstract

The Hubble parameter ($H(z)$) is a function of the redshift and a reliable measurement is very important to understand the expansion history of the Universe. In this work, we perform full-spectrum fitting using BAGPIPES on more than four thousand massive, passively evolving galaxies released by the DESI collaboration to estimate their cosmological-independent stellar ages and star-formation histories, and derive a new measurement of $H(z=0.12)=71.33 \pm 4.20~{\rm km~s^{-1}~Mpc^{-1}}$, which is well consistent with those derived in other ways.

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Ze-fan Wang, Lei Lei, Yi-zhong Fan. 2026-01-12. New $H(z)$ measurement at Redshift = 0.12 with DESI Data Release 1. https://doi.org/10.3847/1538-4357/ae610a

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