Measurements of Higgs boson production via gluon fusion and vector boson fusion in the diphoton decay channel at $\sqrt{s} = 13$ TeV

Measurements of the Higgs boson production cross sections with the Higgs boson decaying into a pair of photons are reported. Events with two photons are selected from a sample of proton-proton collisions at a center-of-mass energy $\sqrt{s}=13~\mathrm{TeV}$ collected by the CMS detector at the LHC in 2016 and 2017, corresponding to an integrated luminosity of $77.4~\mathrm{fb}^{-1}$. Cross sections for gluon fusion and vector boson fusion production, normalized to the corresponding standard model predictions, are measured to be $1.15_{-0.15}^{+0.15}$ and $0.8_{-0.3}^{+0.4}$, respectively. These production modes are further measured in kinematic regions within the simplified template cross section framework. All results are found to be in agreement with the standard model expectations.