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Collins function and the single transverse spin asymmetry
1Nuclear Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
Physical Review Letters
|October 2, 2009
Summary
We studied the Collins mechanism for single transverse spin asymmetry. The Collins function is universal in this approach, consistent with other methods in deep inelastic scattering.
Area of Science:
- High Energy Physics
- Quantum Chromodynamics
- Particle Physics
Background:
- Single transverse spin asymmetry is a key phenomenon in high energy physics.
- Understanding this asymmetry requires exploring the Collins mechanism.
- The collinear factorization approach provides a framework for these studies.
Purpose of the Study:
- To investigate the Collins mechanism within the collinear factorization approach.
- To identify and analyze the twist-three fragmentation function relevant to this mechanism.
- To determine the universality of the Collins function.
Main Methods:
- Utilizing the collinear factorization approach.
- Identifying the twist-three fragmentation function.
- Calculating the Collins function.
Main Results:
- The Collins function was identified within the collinear factorization approach.
- The calculated Collins function was shown to be universal.
- Consistency was demonstrated between transverse momentum dependent and twist-three collinear approaches for semi-inclusive hadron production in deep inelastic scattering.
Conclusions:
- The Collins mechanism is effectively described by the collinear factorization approach.
- The universality of the Collins function is established.
- The findings reconcile different theoretical frameworks in the intermediate transverse momentum region.
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