Study of Events with Two Leptons in the Final State to Investigate Properties of the Standard Model Higgs Boson and Search for a Heavy Higgs Boson in the h/H → WW() → lνlν Decay in pp Collisions at 13 TeV with the ATLAS Detector at the LHC

The authors, members of the ATLAS Higgs boson working group (HWW), studied events with two leptons in the h / H → WW ( * ) → lνlν decay in pp collisions at 13 TeV using the ATLAS detector at the LHC. The complete data sample recorded during 2015–2018 exposures, which corresponds to an integrated luminosity of 139 fb –1 , was used in the analysis. Attention was focused on the properties of forward going hadron jets. Such jets accompany Higgs boson production through vector boson fusion. Two jet reconstruction algorithms, EMTopo and PFlow, are compared. The second algorithm is chosen for further analyses as more reliable at high LHC luminosity. Jet kinematics is studied separately for the exposures at various differential luminosities. The first results of the analysis of control regions of the main sources of background to the production of the heavy Higgs boson based on complete 13 TeV statistics are presented.