Aspects of pQCD at a 100 TeV future hadron collider

TL;DR

This paper explores QCD phenomena at a hypothetical 100 TeV collider, addressing theoretical challenges, scaling patterns, jet substructure, Higgs production, and background estimates for new physics searches.

Contribution

It provides novel insights into high-energy QCD processes, jet substructure, and the applicability of effective theories at a future collider energy of 100 TeV.

Findings

Scaling patterns in multijet production allow extrapolation to high multiplicities.

Predictions for jet substructure match analytical resummations and boosted decay expectations.

Assessment of Standard Model backgrounds for new physics at 100 TeV.

Abstract

In this publication we consider particle production at a future circular hadron collider with 100 TeV centre of mass energy within the Standard Model, and in particular their QCD aspects. Accurate predictions for these processes pose severe theoretical challenges related to large hierarchies of scales and possible large multiplicities of final state particles. We investigate scaling patterns in multijet-production rates allowing to extrapolate predictions to very high final-state multiplicities. Furthermore, we consider large-area QCD jets and study the expectation for the mean number of subjets to be reconstructed from their constituents and confront these with analytical resummed predictions and with the expectation for boosted hadronic decays of top-quarks and W-bosons. We also discuss the validity of Higgs-Effective-Field-Theory in making predictions for Higgs-boson production in association with jets. Finally, we consider the case of New Physics searches at such a 100 TeV hadron-collider machine and discuss the expectations for corresponding Standard-Model background processes.