Combined measurement of the total and differential cross sections in the $H \rightarrow \gamma \gamma$ and the $H \rightarrow ZZ^* \rightarrow 4\ell$ decay channels at $\sqrt{s} = $13 TeV with the ATLAS detector

Combined measurements of the total and differential cross sections of Higgs boson production are performed with proton-proton collisions recorded by the ATLAS detector at the Large Hadron Collider. The data correspond to an integrated luminosity of 139 $\textrm{fb}^{-1}$ produced at a center-of-mass energy of 13 TeV. The cross sections are obtained from the measured $H \rightarrow ZZ^* \rightarrow 4\ell$ and $H \rightarrow \gamma \gamma$ event yields, which are combined accounting for luminosity, detector effects, acceptances, and branching fractions. The measured total Higgs boson production cross section is 55.4$^{+4.3}_{-4.2}$~pb, in agreement with the Standard Model prediction. A differential cross-section measurement is also performed as a function of the Higgs boson transverse momentum. The results from the two decay channels are found to be compatible with each other, and their combination agrees with the Standard Model predictions.