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Two-Loop Six Gluon All-Plus Helicity Amplitude.

David C Dunbar1, Warren B Perkins1

  • 1College of Science, Swansea University, Swansea SA2 8PP, United Kingdom.

Physical Review Letters
|August 20, 2016
PubMed
Summary
This summary is machine-generated.

We derived a two-loop analytic expression for a specific six-point amplitude in Quantum Chromodynamics (QCD). This calculation simplifies understanding complex particle interactions in high-energy physics.

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Area of Science:

  • High-energy physics
  • Quantum Chromodynamics (QCD)
  • Theoretical particle physics

Background:

  • Scattering amplitudes are fundamental to understanding particle interactions.
  • Calculating multi-particle amplitudes in Quantum Chromodynamics (QCD) is computationally intensive.
  • Two-loop precision is often required for comparing theory with experimental data.

Purpose of the Study:

  • To present an analytic expression for the six-point all-plus helicity amplitude in QCD.
  • To provide a compact, calculable form for these complex amplitudes.
  • To advance theoretical tools for high-energy scattering processes.

Main Methods:

  • Analytic computation of scattering amplitudes.
  • Focus on the six-point all-plus helicity configuration.
  • Two-loop perturbative expansion in QCD.
  • Organization of results by singularity structure.

Main Results:

  • An exact, compact analytic expression for the two-loop six-point all-plus helicity amplitude.
  • Identification and computation of the rational terms.
  • The expression is organized to reveal its analytic properties.

Conclusions:

  • The derived expression offers a significant step forward in calculating multi-leg amplitudes in QCD.
  • This result facilitates more precise theoretical predictions in high-energy physics.
  • The methodology can be extended to other amplitudes and processes.