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Updated: Mar 9, 2026
07:46
Setting Limits on Supersymmetry Using Simplified Models
Published on: November 15, 2013
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Golden Probe of Electroweak Symmetry Breaking
Yi Chen1,2, Joe Lykken3, Maria Spiropulu2
1CERN, European Organization for Nuclear Research, Geneva, Switzerland CH-1211.
Physical Review Letters
|December 24, 2016
Summary
Investigating Higgs boson decays to four leptons (h→4ℓ) can determine the sign of the Higgs-to-weak-boson coupling ratio (λWZ). This crucial measurement probes electroweak symmetry breaking and custodial symmetry at the Large Hadron Collider.
Area of Science:
- Particle Physics
- High Energy Physics
- Electroweak Symmetry Breaking
Background:
- The Higgs coupling ratio to WW and ZZ pairs (λWZ) is key to understanding electroweak symmetry breaking.
- Custodial symmetry, a property of the gauge boson mass matrix, is measured by λWZ.
Purpose of the Study:
- To demonstrate that Higgs decays to four leptons (h→4ℓ) are sensitive to the sign and magnitude of λWZ.
- To establish the significance of determining the sign of λWZ for understanding the Higgs boson's custodial representation.
Main Methods:
- Analysis of tree-level and one-loop interference effects in h→4ℓ decays.
- Utilizing high-luminosity 13 TeV Large Hadron Collider data for sensitivity analysis.
Main Results:
- Higgs decays to four leptons (h→4ℓ) can directly determine the overall sign of λWZ.
- The sign determination is primarily achieved through interference effects, not just decay rates.
- High-luminosity LHC offers excellent prospects for measuring λWZ sign and magnitude.
Conclusions:
- h→4ℓ decays provide a unique and independent probe of electroweak and custodial symmetries.
- Measurements are largely independent of other Higgs couplings and top quark Yukawa couplings.
- Establishing the sign of λWZ clarifies the Higgs boson's custodial representation.
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