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Threshold resummation in momentum space from effective field theory
Thomas Becher1, Matthias Neubert
1Fermi National Accelerator Laboratory, Batavia, Illinois 60510, USA.
Physical Review Letters
|October 10, 2006
Summary
This study introduces a novel momentum-space method for threshold resummation of Sudakov logarithms in deep-inelastic structure functions. The approach transparently separates physical scales from nonperturbative hadronic physics.
Area of Science:
- High Energy Physics
- Quantum Chromodynamics (QCD)
Background:
- Deep-inelastic scattering (DIS) structure function F2 is crucial for understanding hadron structure.
- Threshold resummation of Sudakov logarithms is essential for theoretical predictions in the endpoint region (x-->1).
Purpose of the Study:
- To develop a momentum-space method for threshold resummation of Sudakov logarithms for F2.
- To derive an all-order formula for the short-distance coefficient function C.
- To transparently separate contributions from physical scales and nonperturbative hadronic physics.
Main Methods:
- Utilizing soft-collinear effective theory (SCET).
- Performing threshold resummation directly in momentum space.
- Deriving an exact solution to the integro-differential evolution equation for the jet function.
Main Results:
- An explicit all-order formula for the short-distance coefficient function C is derived.
- Contributions from physical scales (Q^2 and Q^2(1-x)) are clearly separated from nonperturbative hadronic physics.
- A transparent separation of perturbative and nonperturbative contributions is achieved.
Conclusions:
- The developed momentum-space resummation method provides a transparent framework for analyzing F2 structure function.
- The methodology is applicable to various other hard QCD processes.
- This work advances theoretical predictions in high-energy QCD.
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