In their searches for the Standard Model (SM) Higgs boson in the mass range 115-1000 GeV, both ATLAS and CMS Collaborations observed a narrow four-lepton resonance with a mass near 125 GeV with local significances in excess of 5?. In the combination of the ATLAS and CMS H→ZZ→4ℓ measurements, the mass of the observed boson was found to be 125.15 ± 0.37 (stat) ± 0.15 (syst) GeV. The event rates attributed to the signal and the studied differential cross sections were compatible with the SM Higgs boson hypothesis. Kinematic properties of leptons in signal candidate events agreed with those expected for a state with spinparity quantum numbers of the SM Higgs boson (JP = 0+) and strongly disfavoured states with alternative quantum numbers or 0+ states with non-SM-like tensor structures of their couplings to Z bosons. The yield and kinematic properties of events in the high four-lepton mass region allowed one to probe off-shell production of the discovered boson and set model-dependent upper limits on its natural width.
|Title of host publication||Discovery of the Higgs Boson|
|Editors||Aleandro Nisati, Vivek Sharma|
|ISBN (Print)||978-9814425445 , 978-9814425872|
|Publication status||Published - Oct 2016|