Measurements of production cross sections of polarized same-sign W boson pairs in association with two jets in proton-proton collisions at $\sqrt{s} =$ 13 TeV

Bruno, Giacomo [UCL] Bury, Florian [UCL] Caputo, Claudio [UCL] David, Pieter [UCL] Delaere, Christophe [UCL] Delcourt, Martin [UCL] Donertas, Izzeddin Suat [UCL] Giammanco, Andrea [UCL] Lemaitre, Vincent [UCL] Mondal, Kuntal [UCL] Prisciandaro, Jessica [UCL] Taliercio, Angela [UCL] Teklishyn, Maksym [UCL] Vischia, Pietro [UCL] Wertz, Sébastien [UCL] Wuyckens, Sophie [UCL] CMS et al.

The first measurements of production cross sections of polarized same-sign W±W± boson pairs in proton-proton collisions are reported. The measurements are based on a data sample collected with the CMS detector at the LHC at a center-of-mass energy of 13TeV , corresponding to an integrated luminosity of 137fb−1 . Events are selected by requiring exactly two same-sign leptons, electrons or muons, moderate missing transverse momentum, and two jets with a large rapidity separation and a large dijet mass to enhance the contribution of same-sign W±W± scattering events. An observed (expected) 95% confidence level upper limit of 1.17 (0.88) fbis set on the production cross section for longitudinally polarized same-sign W±W± boson pairs. The electroweak production of same-sign W±W± boson pairs with at least one of the W bosons longitudinally polarized is measured with an observed (expected) significance of 2.3 (3.1) standard deviations.