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Bounds on transverse momentum dependent distribution and fragmentation functions
Bacchetta1, Boglione, Henneman
1Department of Theoretical Physics, Faculty of Science, Vrije Universiteit, De Boelelaan 1081, NL-1081 HV Amsterdam, The Netherlands.
Physical Review Letters
|September 16, 2000
Summary
We established bounds for distribution and fragmentation functions in deep inelastic leptoproduction and Drell-Yan processes. These bounds, derived from matrix element positivity, guide the estimation of azimuthal and spin asymmetries.
Area of Science:
- High Energy Physics
- Quantum Chromodynamics
Background:
- Deep inelastic leptoproduction and Drell-Yan processes are crucial for probing the structure of hadrons.
- Distribution and fragmentation functions are key components in theoretical calculations for these processes.
Purpose of the Study:
- To derive fundamental bounds on distribution and fragmentation functions.
- To provide guidance for estimating asymmetries in high-energy scattering experiments.
Main Methods:
- The study employs theoretical analysis based on the positivity of defining matrix elements.
- Bounds are derived for functions appearing at the leading order of relevant processes.
Main Results:
- Established theoretical bounds on distribution and fragmentation functions.
- Demonstrated the utility of these bounds in estimating azimuthal and spin asymmetries.
Conclusions:
- The derived bounds offer essential constraints for theoretical models.
- Positivity of matrix elements provides a powerful tool for understanding particle production processes.
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