Abstract
A test of CP invariance in Higgs boson production via vector-boson fusion using the method of the Optimal Observable is presented. The analysis exploits the decay mode of the Higgs boson into a pair of τ leptons and is based on 20.3 fb−1 of proton–proton collision data at √s = 8 TeV collected by the ATLAS experiment at the LHC. Contributions from CP-violating interactions between the Higgs boson and electroweak gauge bosons are described in an effective field theory framework, in which the strength of CP violation is governed by a single parameter d~. The mean values and distributions of CP-odd observables agree with the expectation in the Standard Model and show no sign of CP violation. The CP-mixing parameter d~ is constrained to the interval (−0.11,0.05) at 68% confidence level, consistent with the Standard Model expectation of d~=0.
Original language | English |
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Article number | 658 |
Pages (from-to) | 1-25 |
Number of pages | 25 |
Journal | European Physical Journal C: Particles and Fields |
Volume | 76 |
Early online date | 29 Nov 2016 |
DOIs | |
Publication status | Published - Dec 2016 |