Updated 1.1% Precision Values of the Hubble Constant with Corrected Pantheon+ and Dark Energy Survey (DES)-DOVEKIE Type Ia Supernovae

Abstract

We update the Hubble constant measurement with corrected Pantheon+ and DES-DOVEKIE supernovae. The use of DES-DOVEKIE here is the first application of DES-DOVEKIE to a distance-ladder $H_0$ determination. Recent reanalyses of supernova datasets have put Pantheon+, DES-DOVEKIE, and Union3.1 samples on the same footing with regard to the evidence of dynamical dark energy ($3.2$--$3.4\sigma$), and thus an update on the Hubble constant is the next logical step. The $H_0$ Distance Network (H0DN) baseline is $73.499\pm 0.809$ km s${}^{-1}$ Mpc${}^{-1}$, a $7.1\sigma$ tension with the cosmic microwave background (CMB) determination in a $\Lambda$ cold-dark-matter ($\Lambda$CDM) cosmology, $H_0^{\mathrm{CMB},\mathrm{\Lambda CDM}}=67.24\pm 0.35$ km s${}^{-1}$ Mpc${}^{-1}$. A revised host-mass correction applied to the older Pantheon+ changes 114 of the total 1701 apparent-magnitude rows. The calibrator supernovae are not affected, but 52 of the 277 Hubble-flow rows are. Applying only these magnitude corrections, with the H0DN covariance, redshifts, and velocities unchanged, gives $H_0=73.264\pm 0.806$ km s${}^{-1}$ Mpc${}^{-1}$ and a $6.85\sigma$ Hubble tension. This is our main baseline result and the update for the astrophysics community. Alternatively, replacing the complete Hubble-flow treatment with the corrected Pantheon+ data gives $73.139\pm 0.791$ km s${}^{-1}$ Mpc${}^{-1}$ and $6.82\sigma$. For DES-DOVEKIE, 220 supernovae span $0.025\le z_{\mathrm{HD}}\le 0.151$ in Hubble-diagram redshift, and 196 of them overlap with corrected Pantheon+. These overlaps determine the offset used to place the public DES-DOVEKIE distance moduli on the H0DN apparent-magnitude scale. Holding this offset fixed gives $H_0=73.267\pm 0.828$ km s${}^{-1}$ Mpc${}^{-1}$ and a $6.70\sigma$ tension. Extending to $z_{\mathrm{HD}}\simeq 0.3$ raises $H_0$. However, both rises are smaller than the H0DN uncertainty. Neither update resolves the Hubble tension. (abridged)

Comments: 10 pages, 2 figures