Large Effects from Small QCD Instantons: Making Soft Bombs at Hadron Colliders

TL;DR

This paper presents the first comprehensive calculation and simulation of QCD instanton-induced processes in proton-proton collisions, proposing a strategy for their experimental detection at hadron colliders.

Contribution

It provides the first full quantum-corrected calculation of QCD instanton processes, including implementation in an MC generator and an experimental observation strategy.

Findings

First quantum-corrected calculation of QCD instantons in proton collisions

Implementation of instanton processes in a Monte Carlo event generator

Proposed experimental strategy for observing instanton effects

Abstract

It is a common belief that the last missing piece of the Standard Model of particles physics was found with the discovery of the Higgs boson at the Large Hadron Collider. However, there remains a major prediction of quantum tunnelling processes mediated by instanton solutions in the Yang-Mills theory, that is still untested in the Standard Model. The direct experimental observation of instanton-induced processes, which are a consequence of the non-trivial vacuum structure of the Standard Model and of quantum tunnelling in QFT, would be a major breakthrough in modern particle physics. In this paper, we present for the first time a full calculation of QCD instanton-induced processes in proton-proton collisions accounting for quantum corrections due to both initial and final state gluon interactions, a first implementation in an MC event generator as well as a basic strategy how to observe these effects experimentally.