Parton Distribution Functions and their Generalizations

TL;DR

This paper introduces parton distribution functions and their generalizations, explaining their theoretical background, how they are measured, and what they reveal about the internal structure of hadrons in high-energy physics.

Contribution

It provides a comprehensive overview of the theoretical foundations, historical context, and recent developments in the study of parton distribution functions and their generalizations.

Findings

Clarifies the connections between different distribution functions

Describes processes to access these functions experimentally

Summarizes recent advances in understanding hadron structure

Abstract

This article is an introduction to parton distribution functions and their generalizations which describe the quark and gluon structure of hadrons, and can be measured in various high-energy scattering processes. We provide the theoretical background, highlight both historical and recent developments, explain the connections between the different functions, and expose in which processes these functions can be accessed and what we can learn from them about hadron structure.