Measurements of gluon-gluon fusion and vector-boson fusion Higgs boson production cross-sections in the $H\to W{W}^{\ast }\to e\nu \mu \nu$ decay channel in $pp$ collisions at $\sqrt{s}=13$ TeV with the ATLAS detector

Higgs boson production cross-sections in proton-proton collisions are measured in the $H\to W{W}^{\ast }\to e\nu \mu \nu$ decay channel. The proton-proton collision data were produced at the Large Hadron Collider at a centre-of-mass energy of 13 TeV and recorded by the ATLAS detector in 2015 and 2016, corresponding to an integrated luminosity of 36.1 fb${}^{-1}$. The product of the $H\to W{W}^{\ast }$ branching fraction times the gluon-gluon fusion and vector-boson fusion cross-sections are measured to be $11.4 ^{+1.2}{-1.1} ($\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{t}\mathrm{.}$) ^{+1.8}{-1.7}($\mathrm{s}\mathrm{y}\mathrm{s}\mathrm{t}\mathrm{.}$)$ $\mathrm{p}\mathrm{b}$ and $0.50 ^{+0.24}_{-0.22} ($\mathrm{s}\mathrm{t}\mathrm{a}\mathrm{t}\mathrm{.}$) \pm 0.17($\mathrm{s}\mathrm{y}\mathrm{s}\mathrm{t}\mathrm{.}$)$ $\mathrm{p}\mathrm{b}$, respectively, in agreement with the Standard Model predictions.