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Perturbative QCD analysis of local duality in a fixed w2 framework
1University of Virginia, Charlottesville 22901, USA.
Physical Review Letters
|October 26, 2002
Summary
We analyzed nucleon structure function data to understand parton-hadron duality using perturbative quantum chromodynamics (QCD). Our fixed W2 framework revealed a breakdown in the twist-4 approximation, impacting parton distribution evolution.
Area of Science:
- High-energy particle physics
- Quantum Chromodynamics (QCD)
Background:
- Understanding nucleon structure functions is crucial for probing the fundamental constituents of matter.
- Parton-hadron duality is a key concept linking high-energy scattering data to the properties of confined quarks and gluons.
Purpose of the Study:
- To quantitatively analyze parton-hadron duality using perturbative QCD.
- To investigate the Q2 dependence of the F2 nucleon structure function at large x.
- To explore a novel framework based on fixed W2, differing from previous fixed x analyses.
Main Methods:
- Analysis of large x F2 nucleon structure function data.
- Application of a fixed W2 framework for studying Q2 dependence.
- Perturbative QCD calculations incorporating renormalon-type improvements.
Main Results:
- A breakdown of the twist-4 approximation was identified.
- The breakdown affects the initial evolution of parton distributions.
- A renormalon-type improvement at O(1/Q(4)) was incorporated.
Conclusions:
- The fixed W2 approach provides new insights into parton-hadron duality.
- The twist-4 approximation has limitations at certain kinematic regimes.
- Perturbative QCD calculations with improvements are essential for accurate descriptions of nucleon structure.
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