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Higgs couplings: disentangling new physics with off-shell measurements
Giacomo Cacciapaglia1, Aldo Deandrea1, Guillaume Drieu La Rochelle1
1Université de Lyon, F-69622 Lyon, France and Université Lyon 1, Villeurbanne, CNRS/IN2P3, UMR5822, Institut de Physique Nucléaire de Lyon, F-69622 Villeurbanne Cedex, France.
Physical Review Letters
|November 29, 2014
Summary
Researchers explored off-shell Higgs boson measurements to better understand its properties. This study demonstrates a more flexible interpretation of the high-mass gg→ZZ cross-section data, offering model-independent insights into Higgs boson couplings.
Area of Science:
- High Energy Physics
- Particle Physics
- Quantum Field Theory
Background:
- The Higgs boson, a scalar resonance, has been extensively studied through on-shell production and decay channels.
- Off-shell measurements offer a complementary approach to probe Higgs boson properties beyond its mass peak.
- Previous interpretations of off-shell data, like the high-mass gg→ZZ cross-section by CMS, relied on specific assumptions about Higgs couplings.
Purpose of the Study:
- To investigate the potential of off-shell measurements for a more model-independent characterization of the Higgs boson.
- To re-interpret the CMS measurement of the high-invariant mass gg→ZZ cross-section.
- To demonstrate a less restrictive approach to constraining Higgs boson properties using off-shell data.
Main Methods:
- Analysis of the high-invariant mass cross-section for the process gg→ZZ, which includes Higgs boson contributions.
- Development of a framework for interpreting off-shell measurements with reduced reliance on prior assumptions about Higgs couplings.
- Comparison of model-independent interpretations with previous model-dependent constraints on Higgs boson width.
Main Results:
- The study shows that the high-mass gg→ZZ cross-section measurement can be interpreted in a more model-independent manner.
- This approach allows for broader constraints on Higgs boson properties without assuming specific coupling behaviors.
- The findings highlight the value of off-shell measurements for comprehensive Higgs boson studies.
Conclusions:
- Off-shell Higgs boson measurements, particularly the gg→ZZ cross-section, provide valuable, model-independent insights.
- The presented interpretation method offers greater flexibility in probing Higgs boson couplings and properties.
- This work encourages further exploration of off-shell phenomena for a complete understanding of the Standard Model.
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