0000000000649860

AUTHOR

Stefan Alte

showing 3 related works from this author

Effective field theory after a new-physics discovery

2018

When a new heavy particle is discovered at the LHC or at a future high-energy collider, it will be interesting to study its decays into Standard Model particles using an effective field-theory framework. We point out that the proper effective theory can not be constructed as an expansion in local, higher-dimensional operators; rather, it must be based on non-local operators defined in soft-collinear effective theory (SCET). For the interesting case where the new resonance is a gauge-singlet spin-0 boson, which is the first member of a new sector governed by a mass scale $M$, we show how a consistent scale separation between $M$ and the electroweak scale $v$ is achieved up to next-to-next-to…

Nuclear and High Energy PhysicsParticle physics530 PhysicsPhysics beyond the Standard ModelFOS: Physical sciences10192 Physics Institute01 natural sciencesResonance (particle physics)Standard ModelHigh Energy Physics - Phenomenology (hep-ph)0103 physical sciencesEffective field theoryRenormalization Grouplcsh:Nuclear and particle physics. Atomic energy. Radioactivity3106 Nuclear and High Energy Physics010306 general physicsBosonPhysics010308 nuclear & particles physicsComputer Science::Information RetrievalHigh Energy Physics::PhenomenologyEffective Field TheoriesRenormalization groupHigh Energy Physics - PhenomenologySoft-collinear effective theoryBeyond Standard Modellcsh:QC770-798ResummationElectroweak scaleJournal of High Energy Physics
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Consistent searches for SMEFT effects in non-resonant dijet events

2018

We investigate the bounds which can be placed on generic new-physics contributions to dijet production at the LHC using the framework of the Standard Model Effective Field Theory, deriving the first consistently-treated EFT bounds from non-resonant high-energy data. We recast an analysis searching for quark compositeness, equivalent to treating the SM with one higher-dimensional operator as a complete UV model. In order to reach consistent, model-independent EFT conclusions, it is necessary to truncate the EFT effects consistently at order $1/\Lambda^2$ and to include the possibility of multiple operators simultaneously contributing to the observables, neither of which has been done in prev…

Nuclear and High Energy PhysicsParticle physicsTevatronFOS: Physical sciencesParameter space01 natural sciencesHigh Energy Physics - ExperimentStandard ModelHigh Energy Physics - Experiment (hep-ex)High Energy Physics - Phenomenology (hep-ph)Perturbative QCD0103 physical sciencesEffective field theorylcsh:Nuclear and particle physics. Atomic energy. Radioactivity010306 general physicsLinear combinationPhysicsLarge Hadron Collider010308 nuclear & particles physicsHigh Energy Physics::PhenomenologyEffective Field TheoriesTechnicolor and Composite ModelsObservableWeinberg angleHigh Energy Physics - PhenomenologyBeyond Standard Modellcsh:QC770-798Journal of High Energy Physics
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Consistent Searches for SMEFT Effects in Non-Resonant Dilepton Events

2019

Employing the framework of the Standard Model Effective Field Theory, we perform a detailed reinterpretation of measurements of the Weinberg angle in dilepton production as a search for new-physics effects. We truncate our signal prediction at order $1/\Lambda^2$, where $\Lambda$ denotes the new-physics mass scale, and introduce a theory error to account for unknown contributions of order $1/\Lambda^4$. Two linear combinations of four-fermion operators with distinct angular behavior contribute to dilepton production with growing impact at high energies. We define suitable angular observables and derive bounds on those two linear combinations using data from the Tevatron and the LHC. We find…

Nuclear and High Energy Physics530 PhysicsHigh Energy Physics::PhenomenologyFOS: Physical sciencesEffective Field Theories10192 Physics InstituteHigh Energy Physics - ExperimentHigh Energy Physics - Experiment (hep-ex)High Energy Physics - PhenomenologyHigh Energy Physics - Phenomenology (hep-ph)Beyond Standard Modellcsh:QC770-798lcsh:Nuclear and particle physics. Atomic energy. Radioactivity3106 Nuclear and High Energy Physics
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