Double-logarithmic Scaling of the Structure Function F_2 at small x

TL;DR

This paper analyzes recent experimental data on the structure function F_2 at small x, showing it rises logarithmically with x and Q^2, aligning with theoretical expectations and discussing implications for unitarity at very small x.

Contribution

It provides an analysis of recent data demonstrating a logarithmic rise of F_2 at small x, consistent with theoretical models, and discusses the limitations of current data in observing stronger increases.

Findings

F_2(x,Q^2) rises logarithmically at small x

The observed rise is compatible with theoretical expectations

Stronger increases may violate unitarity but are not supported by current data

Abstract

Recent data on the structure function F_2(x,Q^2) at small values of x are analysed and compared with theoretical expectations. It is shown that the observed rise at small x is consistent with a logarithmic increase, growing logarithmically also with Q^2. A stronger increase, which may be incompatible with unitarity when extrapolated to asymptotically small values of x, cannot be inferred from present data.