Generalized parton distributions

作者：Feldmann T^*

来源：The European Physical Journal - Special Topics, 2007, 140: 135-167.

DOI：10.1140/epjst/e2007-00005-3

These lectures give an introduction to the concept of generalized parton distributions, its phenomenological applications and the implications for the understanding of nucleon structure. We start in Section 1 with a review on nucleon structure functions obtained from deep inelastic scattering and their interpretation in the parton model. The inclusion of QCD corrections requires the factorization of short-distance contributions to partonic cross sections from long-distance dynamics encoded in ( conventional) parton distribution functions (PDFs). This framework will be generalized in Section 2. It is argued that the description of a class of exclusive high-energy processes, like for instance deeply virtual Compton scattering (DVCS), involves generalized parton distributions (GPDs) whose theoretical properties will be discussed in some detail. Section 3 is devoted to the phenomenology of GPDs. We discuss some examples for theoretical parameterizations that can be confronted to experimental data. Finally, Section 4 is devoted to the interpretation of GPDs in impact parameter space ("nucleon tomography") and the connection to the distribution of orbital momentum of partons in a fast-moving nucleon.

• 出版日期2007-1