Combined coupling measurements of the Higgs-like boson with the ATLAS detector using up to 25 fb$^{-1}$ of proton-proton collision data

This note presents an update of the measurements of the properties of the newly discovered boson using the full $pp$ collision data sample recorded by the ATLAS experiment at the LHC for the channels $H \rightarrow\gamma\gamma$, $H\rightarrow ZZ^{(*)} \rightarrow 4l$ and $H \rightarrow WW^{(*)} \rightarrow l \nu l \nu$, corresponding to integrated luminosities of up to 4.8 fb$^{-1}$ at $\sqrt{s}=7\,$TeV and 20.7 fb$^{-1}$ at $\sqrt{s}=8\,$TeV. The combination also includes results from the $H \rightarrow \tau^+ \tau^-$ and $H \rightarrow b\bar{b}$ channels based on $pp$ collision data corresponding to an integrated luminosity of up to 4.7 fb$^{-1}$ at $\sqrt{s}=7\,$TeV and 13 fb$^{-1}$ at $\sqrt{s}=8\,$TeV. The combined signal strength is determined to be $\mu = 1.30 \pm 0.13 \text{(stat)} \pm 0.14 \text{(sys)}$ at a mass of 125.5 GeV. The cross section ratio between vector boson mediated and gluon (top) initiated Higgs boson production processes is found to be $\mu_{\mathrm{VBF}+VH}/\mu_{\mathrm{ggF}+t\bar{t}H}=1.2^{+0.7}_{-0.5}$, giving more than 3$\sigma$ evidence for Higgs-like boson production through vector-boson fusion. Measurements of relative branching fraction ratios between the $H \rightarrow\gamma\gamma$, $H \rightarrow ZZ^{(*)} \rightarrow 4l$ and $H \rightarrow WW^{(*)} \rightarrow l \nu l \nu$ channels, as well as combined fits testing the fermion and vector coupling sector, couplings to $W$ and $Z$ and loop induced processes of the Higgs-like boson show no significant deviation from the Standard Model expectation.