Unitarity Bounds on Effective Field Theories at the LHC

Abstract

Effective Field Theory (EFT) extensions of the Standard Model are tools to compute observables $(e.g.$ cross sections with partonic center-of-mass energy $\sqrt{\hat{s}})$ as a systematically improvable expansion suppressed by a new physics scale $M$. If one is interested in EFT predictions in the parameter space where $M<\sqrt{\hat{s}}$, concerns of self-consistency emerge, which can manifest as a violation of perturbative partial-wave unitarity. However, when we search for the effects of an EFT at a hadron collider with center-of-mass energy $\sqrt{s}$ using an inclusive strategy, we typically do not have access to the event-by-event value of $\sqrt{\hat{s}}$. This motivates the need for a formalism that incorporates parton distribution functions into the perturbative partial-wave unitarity analysis. Developing such a framework and initiating an exploration of its implications is the goal of this work. Our approach opens up a potentially valid region of the EFT parameter space where $M\ll \sqrt{s}$. We provide evidence that there exist valid EFTs in this parameter space. The perturbative unitarity bounds are sensitive to the details of a given search, an effect we investigate by varying kinematic cuts.

38 pages + appendix, 21 figures

References in corpus (47)

• New parton distributions for collider physics
• Constraints on Dark Matter from Colliders
• Confronting lepton flavor universality violation in B decays with high-$p_T$ tau lepton searches at LHC
• Characterising dark matter searches at colliders and direct detection experiments: Vector mediators
• Operator bases, $S$-matrices, and their partition functions
• Constraining Dark Sectors at Colliders: Beyond the Effective Theory Approach
• Effective four-fermion operators in top physics: a roadmap
• On the Validity of the Effective Field Theory for Dark Matter Searches at the LHC Part III: Analysis for the $t$-channel
• Vices and Virtues of Higgs EFTs at Large Energy
• Anomalous Triple Gauge Couplings in the Effective Field Theory Approach at the LHC
• Is SMEFT Enough?
• Study of ${\chi }_{cJ}$ decaying into $\varphi$ $K^{\ast }(892)$ $\bar{K}$
• Robust collider limits on heavy-mediator Dark Matter
• Effective Theories and Measurements at Colliders
• Signatures of Majorana dark matter with t-channel mediators
• Measurements of production cross sections of WZ and same-sign WW boson pairs in association with two jets in proton-proton collisions at $\sqrt{s}=$ 13 TeV
• Constraints on mediator-based dark matter and scalar dark energy models using $\sqrt{s}=13$ TeV $pp$ collision data collected by the ATLAS detector
• Novel measurements of anomalous triple gauge couplings for the LHC
• Next-to-Leading Order Predictions for Dark Matter Production at Hadron Colliders
• Unitarity Constraints on Dimension-Six Operators
• Unitarity Constraints on Dimension-six Operators II: Including Fermionic Operators
• Unitarity Violation and the Geometry of Higgs EFTs
• SMEFT analysis of vector boson scattering and diboson data from the LHC Run II
• Precision Probes of QCD at High Energies
• Measurements of pp $\to$ ZZ production cross sections and constraints on anomalous triple gauge couplings at $\sqrt{s}=$ 13 TeV
• Measurements of the pp $\to$ WZ inclusive and differential production cross section and constraints on charged anomalous triple gauge couplings at $\sqrt{s}=$ 13 TeV
• MeV Dark Matter: Model Independent Bounds
• Precision diboson measurements at hadron colliders
• Non-Decoupling New Particles
• Top-philic heavy resonances in four-top final states and their EFT interpretation
• High-energy EFT probes with fully differential Drell-Yan measurements
• Search for new physics in top quark production with additional leptons in proton-proton collisions at $\sqrt{s}=$ 13 TeV using effective field theory
• The Last Gasp of Dark Matter Effective Theory
• Measurements of $W^{+}{W}^{-}+\ge 1$jet production cross-sections in $pp$ collisions at $\sqrt{s}=13$TeV with the ATLAS detector
• A sensitivity study of VBS and diboson WW to dimension-6 EFT operators at the LHC
• Higgs Coupling Measurements and the Scale of New Physics
• Measurement of the W$\gamma$ production cross section in proton-proton collisions at $\sqrt{s}=$ 13 TeV and constraints on effective field theory coefficients
• Extract the energy scale of anomalous $\gamma \gamma \to W^{+}{W}^{-}$ scattering in the vector boson scattering process using artificial neural networks
• Probing effective field theory operators in the associated production of top quarks with a Z boson in multilepton final states at $\sqrt{s}=$ 13 TeV
• Same-sign WW Scattering in the HEFT: Discoverability vs. EFT Validity
• Setting limits on Effective Field Theories: the case of Dark Matter
• Bootstrap and Amplitudes: A Hike in the Landscape of Quantum Field Theory
• Dark matter relic density from conformally or disformally coupled light scalars
• Effective field theory versus UV-complete model: vector boson scattering as a case study
• Effective field theory analysis of dark matter-standard model interactions with spin one mediators
• Thermal WIMPs and the Scale of New Physics: Global Fits of Dirac Dark Matter Effective Field Theories
• Fermionic Singlet Dark Matter in One-Loop Solutions to the $R_K$ Anomaly: A Systematic Study

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• On the EFT validity for Drell-Yan tails at the LHC
• Co-interacting dark matter and conformally coupled light scalars
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