Collectivity and manifestations of minimum-bias jets in high-energy nuclear collisions

TL;DR

This paper reviews how minimum-bias jets, rather than collective flow, dominate hadron production in high-energy nuclear collisions, supported by a two-component model analysis of particle spectra from SPS to LHC energies.

Contribution

It introduces a two-component model linking jet properties to particle spectra, challenging the interpretation of flow phenomena as jet manifestations in high-energy collisions.

Findings

MB jets dominate hadron production near midrapidity.

Spectrum hard component relates to isolated jet properties.

The model accurately predicts mean transverse momentum systematics.

Abstract

Collectivity, as interpreted to mean flow of a dense medium in high-energy A-A collisions described by hydrodynamics, has been attributed to smaller collision systems -- p-A and even p-p collisions -- based on recent analysis of LHC data. However, alternative methods reveal that some data features attributed to flows are actually manifestations of minimum-bias (MB) jets. In this presentation I review the differential structure of single-particle $p_t$ spectra from SPS to LHC energies in the context of a two-component (soft + hard) model (TCM) of hadron production. I relate the spectrum hard component to measured properties of isolated jets. I use the spectrum TCM to predict accurately the systematics of ensemble-mean $\bar p_t$ in p-p, p-A and A-A collision systems over a large energy interval. Detailed comparisons of the TCM with spectrum and correlation data suggest that MB jets play a dominant role in hadron production near midrapidity. Claimed flow phenomena are better explained as jet manifestations agreeing quantitatively with measured jet properties.