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Two-loop Sudakov form factor in a theory with a mass gap
Bernd Feucht1, Johann H Kühn, Alexander A Penin
1Institut für Theoretische Teilchenphysik, Universität Karlsruhe, 76128 Karlsruhe, Germany.
Physical Review Letters
|September 28, 2004
Summary
We computed the two-loop Sudakov form factor in U(1) models, establishing a matching procedure for theories with and without a mass gap. This sets the stage for high-energy electroweak process calculations.
Area of Science:
- High-energy particle physics
- Quantum field theory
Background:
- The Sudakov form factor is crucial for understanding high-energy scattering processes.
- Previous calculations often simplified models, neglecting mass gap effects.
Purpose of the Study:
- To compute the two-loop Sudakov form factor in U(1) models with massive gauge bosons.
- To analyze the form factor in the context of hard and infrared evolution equations.
- To establish a matching procedure between theories with and without a mass gap.
Main Methods:
- Calculation of the two-loop Sudakov form factor in specified U(1) models.
- Analysis using hard and infrared evolution equations.
- Development of a matching procedure for theories with and without a mass gap.
Main Results:
- The two-loop Sudakov form factor was successfully computed for both U(1) and U(1)xU(1) models.
- A novel matching procedure was established, connecting theories with and without a mass gap.
- The results provide a foundation for future calculations of electroweak processes.
Conclusions:
- The study successfully computed the two-loop Sudakov form factor in relevant theoretical frameworks.
- The established matching procedure is a key step towards more complete high-energy physics calculations.
- This work paves the way for accurate predictions of dominant two-loop corrections to electroweak processes.
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