Determination of spin and parity of the Higgs boson in the decay channel with the ATLAS detector

Studies of the spin and parity quantum numbersof the Higgs bosonin the WW∗ → eνμν final state are presented, based on proton–proton collision data collected by the ATLAS detector at the Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb-1 at a centre-of-mass energy of s=8 TeV. The Standard Modelspin-parity JCP = 0++ hypothesis is compared with alternative hypotheses for both spin and CP. The case where the observed resonance is a mixture of the Standard-Model-like Higgs bosonand CP-even (JCP = 0++) or CP-odd (JCP = 0+-) Higgs bosonin scenarios beyond the Standard Modelis also studied. The data are found to be consistent with the Standard Modelprediction and limits are placed on alternative spin and CP hypotheses, including CP mixing in different scenarios.