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Precision measurements of anomalous quartic couplings of electroweak gauge bosons allow us to search for deviations of the Standard Model predictions and signals of new physics. Here, we obtain the constraints on anomalous quartic gauge couplings using the presently available data on the production of gauge-boson pairs via vector boson fusion. We work in the Higgs effective theory framework and obtain the present bounds on the operator’s Wilson coefficients. We show that the combination of different datasets breaks the degeneracies in analysis with more than one nonvanishing Wilson coefficient. Anomalous quartic gauge boson couplings lead to rapidly growing cross sections and we discuss the impact of a unitarization procedure on the attainable limits.
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This content will become publicly available on February 28, 2026
LHC EFT WG note: Basis for anomalous quartic gauge couplings
In this note, we give a definitive basis for the dimension-eight operators leading to quartic—but no cubic—interactions among electroweak gauge bosons. These are often called anomalous quartic gauge couplings, or aQGCs. We distinguish in particular the CP-even ones from their CP-odd counterparts.
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- Award ID(s):
- 2210533
- PAR ID:
- 10646503
- Publisher / Repository:
- SciPost
- Date Published:
- Journal Name:
- SciPost Physics Community Reports
- ISSN:
- 3051-3197
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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