Logo
ScienceStack
Table of Contents
Fetching ...
Sign In

Structure of non-global logarithms with Cambridge/Aachen clustering

K. Khelifa-Kerfa

Abstract

We determine the structure of both Abelian and non-Abelian non-global logarithms up to four loops for $e^+ e^-$ processes in perturbative QCD, where final-state jets are defined using the Cambridge-Aachen (C/A) clustering algorithm. The calculations are performed within the soft (eikonal) approximation using strong-energy ordering of the final-state partons. The resulting expressions include full colour and complete jet-radius dependence. Compared to the anti-$k_t$ and $k_t$ clustering algorithms, the C/A distribution minimises the impact of these non-global logarithms, making it the preferred choice among the three algorithms.

Structure of non-global logarithms with Cambridge/Aachen clustering

Abstract

We determine the structure of both Abelian and non-Abelian non-global logarithms up to four loops for processes in perturbative QCD, where final-state jets are defined using the Cambridge-Aachen (C/A) clustering algorithm. The calculations are performed within the soft (eikonal) approximation using strong-energy ordering of the final-state partons. The resulting expressions include full colour and complete jet-radius dependence. Compared to the anti- and clustering algorithms, the C/A distribution minimises the impact of these non-global logarithms, making it the preferred choice among the three algorithms.

Paper Structure

This paper contains 9 sections, 30 equations, 9 figures, 4 tables.

Table of Contents

  1. Introduction
  2. Observable and jet algorithm definitions
  3. C/A jet algorithm
  4. Observable distribution
  5. Fixed-order calculations
  6. Three loops
  7. Four loops
  8. All-order treatment
  9. Conclusion

Figures (9)

  • Figure 1: The two-loop CLs and NGLs coefficients for the $k_t$ jet algorithm (from Ref. Khelifa-Kerfa:2024hwx).
  • Figure 2: The three-loop CLs coefficient for the C/A and $k_t$ jet algorithms.
  • Figure 3: The three-loop NGLs coefficients for the C/A and $k_t$ jet algorithms.
  • Figure 4: The sum of CLs and NGLs contributions to the jet mass fraction at three loops for three jet algorithms.
  • Figure 5: The four-loop CLs coefficient for the C/A and $k_t$ jet algorithms.
  • ...and 4 more figures