Interplay between jet production and event activity

Characterize the underlying interplay between jet production and event activity in small collision systems, including how multiplicity selection modifies jet production, fragmentation, and the resulting non-flow correlations.

Background

Non-flow correlations in small collision systems are strongly influenced by jet production, while event-activity or multiplicity selections can bias the sampled jet population. Such biases affect jet rates, transverse-momentum distributions, fragmentation patterns, and two-particle correlation harmonics.

The paper studies this interplay using PYTHIA at RHIC energies and demonstrates substantial multiplicity dependence, but it does not provide a complete, generally applicable understanding of the underlying hard-soft dynamics or establish that the observed behavior applies to experimental data and other collision systems.

References

Whether these hard-soft correlations are purely selection biases that lead to more or fewer jets in the sample, or whether the correlations are indicative of different types of plasmas that are formed when jets are present is an open question.

— Centrality-dependent nuclear modification from hard-soft correlations in the glasma  (2609.29886 - Faraday et al., 24 Sep 2026) in Section 1, Introduction

Despite the development of a variety of techniques for suppressing these contributions, the underlying interplay between jet production and event activity is still not fully understood.

— Study of the multiplicity dependence of non-flow correlations in pp collisions at $\sqrt{s}=200$ GeV using PYTHIA  (2609.11526 - Stojanovic et al., 10 Sep 2026) in Section 1, Introduction