Parton distributions at the dawn of the LHC

TL;DR

This paper reviews the methods and recent progress in determining the parton distribution functions of the nucleon, crucial for precision predictions at the LHC, focusing on extraction techniques, uncertainties, and applications.

Contribution

It provides a comprehensive overview of current approaches, including Hessian and Monte Carlo methods, for extracting PDFs and their uncertainties from experimental data.

Findings

Comparison of Hessian and Monte Carlo methods for PDF determination

Summary of physical processes constraining PDFs

Current status of PDFs for LHC physics

Abstract

We review basic ideas and recent developments on the determination of the parton substructure of the nucleon, in view of applications to precision hadron collider physics. We review the way information on parton distributions (PDFs) is extracted from the data exploiting QCD factorization, and discuss the current main two approaches to parton determination (Hessian and Monte Carlo) and their use in conjunction with different kinds of parton parametrization. We summarize the way different physical processes can be used to constrain different aspects of PDFs. We discuss the meaning, determination and use of parton uncertainties. We briefly summarize the current state of the art on PDFs for LHC physics.