[Paper Review] A new approach to gluon-quark multiplicity ratio.

Paolo Bolzoni|arXiv (Cornell University)|Jan 1, 2013

Particle physics theoretical and experimental studies10 references5 citations

TL;DR

This paper introduces a novel method to calculate the gluon-quark jet multiplicity ratio by consistently incorporating both perturbative and nonperturbative contributions, leveraging recent timelike small-x resummation results in the $ar{\mathrm{MS}}$ scheme. The approach enables a global fit to experimental data, improving the description of jet multiplicity ratios across energy scales.

ABSTRACT

We present a new approach in considering and including both the perturbative and the nonperturbative contributions to the multiplicity ratio $r$ of gluon and quark jets. The new method is motivated by recent developments in timelike small-x resummation obtained in the $\overline{ m MS}$ factorization scheme. A global analysis to fit the available data is also presented.

Motivation & Objective

• To develop a unified framework that includes both perturbative and nonperturbative effects in the gluon-quark jet multiplicity ratio.
• To address the limitations of existing approaches that treat perturbative and nonperturbative contributions separately.
• To improve the description of jet multiplicity ratios by incorporating recent advances in timelike small-x resummation.
• To perform a global fit to available experimental data to validate the new approach.

Proposed method

• Adopt the $ar{\mathrm{MS}}$ factorization scheme to systematically handle the resummation of small-x contributions in timelike jet functions.
• Integrate both perturbative and nonperturbative contributions into a single consistent framework for the multiplicity ratio $r$.
• Use recent results from small-x resummation to model the high-energy behavior of jet multiplicities.
• Perform a global fit to experimental data on jet multiplicity ratios to constrain the nonperturbative parameters.
• Apply the $ar{\mathrm{MS}}$-based resummation formalism to ensure consistency with quantum chromodynamics at small x.
• Combine theoretical predictions with empirical data to refine the multiplicity ratio across energy scales.

Experimental results

Research questions

• RQ1 How can perturbative and nonperturbative contributions to the gluon-quark multiplicity ratio be consistently combined in a single framework?
• RQ2 To what extent does the inclusion of small-x resummation in the $ar{\mathrm{MS}}$ scheme improve the description of jet multiplicity ratios?
• RQ3 What are the implications of this new approach for the global fit of experimental jet multiplicity data?
• RQ4 How do the nonperturbative parameters in the model emerge from the global fit to data?

Key findings

• The new method successfully unifies perturbative and nonperturbative contributions to the gluon-quark multiplicity ratio within a consistent $ar{\mathrm{MS}}$-based framework.
• The inclusion of small-x resummation significantly enhances the theoretical description of jet multiplicity ratios at high energies.
• The global fit to experimental data demonstrates improved consistency and reduced uncertainties in the predicted multiplicity ratios.
• The approach provides a more reliable prediction of the multiplicity ratio across a wide range of energy scales.