Small-x, Diffraction and Vector Mesons

TL;DR

This paper reviews recent theoretical and experimental advances in small-x deep inelastic scattering, focusing on the dipole picture, nonlinear saturation effects, and progress in exclusive and diffractive processes, especially in ultraperipheral collisions.

Contribution

It compares collinear factorization and the dipole picture, and discusses next-to-leading order calculations in the nonlinear saturation regime.

Findings

Enhanced understanding of small-x dynamics in deep inelastic scattering

Progress in NLO calculations within the saturation regime

Experimental advances in ultraperipheral nucleus collisions

Abstract

This talk discusses recent progress in some topics relevant for deep inelastic scattering at small x. We discuss first differences and similarities between conventional collinear factorization and the dipole picture of deep inelastic scattering. Many of the recent theoretical advances at small x are related to taking calculations in the nonlinear saturation regime to next-to-leading order accuracy in the QCD coupling. On the experimental side significant recent progress has been made in exclusive and diffractive processes, in particular in ultraperipheral nucleus-nucleus collisions.