A<sc>bstract</sc> We study Higgs boson production via vector boson fusion at the LHC, focusing on the processpp→H+jjand capturing the leading energy-enhanced contributions within the Standard Model Effective Field Theory (SMEFT) up to order 1/Λ4. Employing energy-scaling arguments, we predict the magnitude of each higher-dimensional operator’s contribution. Utilizing the geometric formulation of SMEFT, our analysis incorporates dimension-eight operators not previously considered. We find that the kinematics of vector boson fusion — characterized by two highly forward jets — tend to suppress contributions from higher-dimensional operators, requiring a lower scale Λ for SMEFT effects to become observable. This suggests that the SMEFT remains valid for lower Λ than expected. Combined with the fact that LEP constrains the dimension-six operators with the most considerable impact on vector boson fusion, a regime exists where dimension-eight operators can have significant effects. In many cases, these dimension-eight operators also influence associated production processes likepp→HV(jj), though differences in analysis cuts and kinematics mean this is not always the case. Our findings provide insights that could refine the search for SMEFT signals in collider experiments.
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Probing lepton number violation: a comprehensive survey of dimension-7 SMEFT
A<sc>bstract</sc> Observation of lepton number violation would represent a groundbreaking discovery with profound consequences for fundamental physics and as such, it has motivated an extensive experimental program searching for neutrinoless double beta decay. However, the violation of lepton number can be also tested by a variety of other observables. We focus on the possibilities of probing this fundamental symmetry within the framework of the Standard Model Effective Field Theory (SMEFT) beyond the minimal dimension-5. Specifically, we study the bounds on ∆L= 2 dimension-7 effective operators beyond the electron flavor imposed by all relevant low-energy observables and confront them with derived high-energy collider limits. We also discuss how the synergy of the analyzed multi-frontier observables can play a crucial role in distinguishing among different dimension-7 SMEFT operators.
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- Award ID(s):
- 2020275
- PAR ID:
- 10508935
- Editor(s):
- NA
- Publisher / Repository:
- JHEP
- Date Published:
- Journal Name:
- Journal of High Energy Physics
- Edition / Version:
- 1
- Volume:
- 2024
- Issue:
- 5
- ISSN:
- 1029-8479
- Page Range / eLocation ID:
- 154
- Subject(s) / Keyword(s):
- None
- Format(s):
- Medium: X Size: 1.72MB Other: pdf
- Size(s):
- 1.72MB
- Sponsoring Org:
- National Science Foundation
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