Observables for possible QGP signatures in central pp collisions

TL;DR

This paper investigates potential signatures of quark-gluon plasma in high-multiplicity proton-proton collisions by analyzing jet properties and collective effects, aiming to distinguish small- and large-scale phenomena.

Contribution

It proposes new observables, like jet energy loss and shapes, to identify quark-gluon plasma signatures in pp collisions, expanding current detection methods.

Findings

Jet energy loss may indicate quark-gluon plasma presence.

Long-range correlations are similar to heavy ion collisions.

New measurements could differentiate collective effects in small and large systems.

Abstract

Proton-proton (pp) data show collective effects, such as long-range azimuthal correlations and strangeness enhancement, which are similar to phenomenology observed in heavy ion collisions. Using simulations with and without explicit existing models of collective effects, we explore new ways to probe pp collisions at high multiplicity, in order to suggest measurements that could help identify the similarities and differences between large- and small-scale collective effects. In particular, we focus on the properties of jets produced in ultra-central pp collisions in association with a Z boson. We consider observables such as jet energy loss and jet shapes, which could point to the possible existence of an underlying quark-gluon plasma, or other new dynamical effects related to the presence of large hadronic densities.