How to discover QCD Instantons at the LHC

Abstract

The Standard Model of particle physics predicts the existence of quantum tunnelling processes across topological inequivalent vacua, known as Instantons. In the electroweak sector, instantons provide a source of baryon asymmetry within the Standard Model. In Quantum Chromodynamics they are linked to chiral symmetry breaking and confinement. The direct experimental observation of Instanton-induced processes would therefore be a breakthrough in modern particle physics. Recently, new calculations for QCD Instanton processes in proton-proton collisions became public, suggesting sizable cross sections as well as promising experimental signatures at the LHC. In this work, we study possible analysis strategies to discover QCD Instanton induced processes at the LHC and derive a first limit based on existing Minimum Bias data.

Work prepared in the context of the CERN TH workshop "Topological Effects in the Standard Model: Instantons, Sphalerons and Beyond at LHC"

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Cited by in corpus (10)

• Measurements of multijet event isotropies using optimal transport with the ATLAS detector
• Hunting for QCD Instantons at the LHC in Events with Large Rapidity Gaps
• Search for soft unclustered energy patterns in proton-proton collisions at 13 TeV
• Bubble Trouble: a Review on Electroweak Baryogenesis
• Searches for QCD instantons with forward proton tagging
• Central Instanton Production
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• A Field Guide to Event-Shape Observables Using Optimal Transport
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