Studying minijets and MPI with rapidity correlations

TL;DR

This paper introduces a new set of observables based on rapidity correlations to distinguish different minijet production mechanisms in high-energy collisions, providing a sensitive tool for model discrimination.

Contribution

It proposes and analyzes novel rapidity correlation observables that effectively differentiate between various minijet production models and parameters.

Findings

Observables are sensitive to minijet production parameters.

Different MC models predict significantly different results.

The observables have high discriminating power across energies and multiplicities.

Abstract

We propose and carry a detailed study of an observable sensitive to different mechanisms of minijet production. The class of observables measures how the transverse momenta of hadrons produced in association with various trigger objects are balanced as a function of rapidity. It is shown that the observables are sensitive to the model parameters relevant to the minijet production mechanisms: low-$p_{\rm T}$ cut-off regulating jet cross-section, transverse distribution of partons in protons, and parton distribution functions. We perform our test at different charge-particle multiplicities and collision energies. The MC models, which describe many features of the LHC data, are found to predict quite different results demonstrating high discriminating power of the proposed observables. We also review mechanisms and components of \sc{Herwig}, \sc{Pythia}, and \sc{Sherpa} Monte Carlo models relevant to the minijet production.