This article presents a search for new resonances decaying into a Z or W boson and a 125 GeV Higgs boson h, and it targets the -b-b, '
+'-b-b, or '+-b-b final states, where
' = e or μ, in proton-proton collisions at p s = 13TeV. The data used correspond to a total integrated luminosity of 139 fb-1 collected by the ATLAS detector during Run 2 of the LHC at CERN. The search is conducted by examining the reconstructed invariant or transverse mass distributions of Zh or Wh candidates for evidence of a localised excess in the mass range from 220 GeV to 5TeV. No significant excess is observed and 95% confidence-level upper limits between 1.3 pb and 0.3 fb are placed on the production cross section times branching fraction of neutral and charged spin-1 resonances and CP-odd scalar bosons.
These limits are converted into constraints on the parameter space of the Heavy Vector
Triplet model and the two-Higgs-doublet model.