Combined measurements of Higgs boson production and decay using up to 80 fb$^{-1}$ of proton--proton collision data at $\sqrt{s}=$ 13 TeV collected with the ATLAS experiment

Combined measurements of Higgs boson production cross-sections, branching fractions and couplings are presented in the Higgs boson decay channels into $\gamma\gamma$, $ZZ^*$, $WW^*$, $\tau\tau$, $\mu\mu$ and $b\bar{b}$, using up to $79.8$ fb$^{-1}$ of proton--proton collision data at $\sqrt{s}=$ 13 TeV collected with the ATLAS experiment. Results are presented for the gluon-gluon fusion and vector-boson fusion processes, and associated production with vector bosons or top quarks. The combined measurement yields an observed (expected) significance for the vector-boson fusion production process of $6.5\sigma$ ($5.3\sigma$). This single-experiment observation follows an earlier observation in the combination of ATLAS and CMS measurements. The results are interpreted in terms of modifiers applied to the Standard Model couplings of the Higgs boson to other particles, and are used to set exclusion limits on new phenomena. No significant deviations from Standard Model predictions are observed.