Measurements of production cross sections of same-sign WW and WZ boson pairs in association with two jets in proton-proton collisions at sqrts = 13 TeV

Measurements of production cross sections of same-sign $\mathrm{W}\mathrm{W}$ and $\mathrm{W}\mathrm{Z}$ boson pairs in association with two jets in proton-proton collisions at $\sqrt{s}$ = 13 TeV at the LHC are reported. The data sample corresponds to an integrated luminosity of $137~\mathrm{fb}^{-1}$ collected with the CMS detector during 2016-18. The measurements are performed in the leptonic decay modes $\mathrm{W}\mathrm{W} \to \ell^\pm\nu\ell'^\pm\nu$ and $\mathrm{W}\mathrm{Z} \to \ell\nu\ell'\ell'$, where $\ell, \ell' = \mathrm{e}$, $\mu$. Differential fiducial cross sections of the invariant masses of the jet and lepton pairs, as well as the leading-lepton transverse momentum are measured for $\mathrm{W}\mathrm{W}$ production and found to be consistent with standard model predictions. Differential fiducial cross sections of the invariant mass of the jet pair are also measured for $\mathrm{W}\mathrm{Z}$ production. An observation of electroweak production of $\mathrm{W}\mathrm{Z}$ boson pairs is reported, with an observed (expected) significance of 6.8 (5.3) standard deviations. Constraints are obtained on the structure of quartic vector boson interactions in the framework of effective theory.