Is it the Higgs? Characterization of the H(125) resonance (spin, parity, tensor structure) with leptonic WW decays

by Rebeca Gonzalez Suarez (Nebraska University)

Wednesday 18 Mar 2015, 13:00 → 14:00 Europe/Brussels

E/3rd floor-E.349 - Seminar room (E.349) (Marc de Hemptinne (chemin du Cyclotron, 2, Louvain-la-Neuve))

The Higgs boson decays to a pair of W bosons around 20% of the times in the Standard Model(SM), making H->WW->2l2nu a discovery channel. This talk will present the main results on Higgs to WW decays from CMS using the full Run-1 data. With about 25 fb-1 of proton-proton collisions at 7 and 8 TeV, strong evidence of the Higgs boson with a mass of around 125 GeV is found with a significance of 4.3 standard deviations. The observed signal cross section times the branching fraction to WW is 0.72+0.20-0.18 times the standard model expectation. Properties are measured using the main analysis. Different spin hypotheses are tested against the SM. A wide range of spin-two models is excluded at a 99% confidence level or higher. Any mixed-parity spin-one state is excluded at greater than 99.999% confidence level. Under the hypothesis that the resonance is a spin-zero boson, the tensor structure of the interactions of the Higgs boson with two vector bosons is investigated using also the ZZ, Zγ, and γγ decays. Tighter constraints on anomalous HVV interactions are obtained by combining the HZZ and HWW measurements.

Slides Rebeca.pdf