Precision studies of the Higgs boson decay channel H -> ZZ -> 4l with MEKD

Abstract

The importance of the H -> ZZ -> 4l "golden" channel was shown by its major role in the discovery, by the ATLAS and CMS collaborations, of a Higgs-like boson with mass near 125 GeV. We analyze the discrimination power of the matrix element method both for separating the signal from the irreducible ZZ background and for distinguishing various spin and parity hypotheses describing a signal in this channel. We show that the proper treatment of interference effects associated with permutations of identical leptons in the four electron and four muon final states plays an important role in achieving the best sensitivity in measuring the properties of the newly discovered boson. We provide a code, MEKD, that calculates kinematic discriminants based on the full leading order matrix elements and which will aid experimentalists and phenomenologists in their continuing studies of the H -> ZZ -> 4l channel.

Major revision: added new sections discussing spin/ parity determination and the importance of using the full matrix element for the same flavor final state (involving both pairings of the leptons). Also added new functionality, including the most general couplings of a spin-0 or spin-2 boson to gluons and Zs, to the publicly-available code, MEKD, presented in this paper. 43 pages, 15 figures

References in corpus (14)

• Observation of a new particle in the search for the Standard Model Higgs boson with the ATLAS detector at the LHC
• Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC
• FeynRules - Feynman rules made easy
• MCFM for the Tevatron and the LHC
• Aspects of CP violation in the HZZ coupling at the LHC
• Observation of Z decays to four leptons with the CMS detector at the LHC
• Measuring spin and CP from semi-hadronic ZZ decays using jet substructure
• From Lagrangians to Events: Computer Tutorial at the MC4BSM-2012 Workshop
• New Developments in MadGraph/MadEvent
• Single-variable asymmetries for measuring the `Higgs' boson spin and CP properties
• Telling the spin of the "Higgs boson" at the LHC
• Extending the Matrix Element Method to Next-to-Leading Order
• Comment on the evidence of the Higgs boson at LHC
• Identification of the 125 GeV Resonance as a Pseudoscalar Quarkonium Meson

Cited by in corpus (9)

• The automated computation of tree-level and next-to-leading order differential cross sections, and their matching to parton shower simulations
• Complete Higgs Sector Constraints on Dimension-6 Operators
• Beyond Geolocating: Constraining Higher Dimensional Operators in $H\to 4\ell$ with Off-Shell Production and More
• Probing the Higgs Couplings to Photons in $h\to 4\ell$ at the LHC
• A note on Higgs decays into $Z$ boson and $J/\Psi ({\rm Y})$
• Angular asymmetries as a probe for anomalous contributions to HZZ vertex at the LHC
• Discoveries far from the Lamppost with Matrix Elements and Ranking
• Quarkonium Resonance Model of the 125 GeV Boson
• Quarkonium resonance identified with the 125 GeV boson