Extracting the rho meson wavefunction from HERA data

TL;DR

This paper extracts the rho meson wavefunction from HERA diffractive photoproduction data, showing agreement with QCD predictions and indicating a preference for a transverse wavefunction with enhanced end-point contributions.

Contribution

It provides the first extraction of the rho meson light-cone wavefunction directly from experimental data, validating QCD-based models.

Findings

Good agreement with QCD sum rule and lattice predictions

Data favor a transverse wavefunction with enhanced end-point contributions

Supports the validity of the light-cone wavefunction approach in meson structure

Abstract

We extract the light-cone wavefunctions of the rho meson using the HERA data on diffractive rho photoproduction. We find good agreement with predictions for the distribution amplitude based on QCD sum rules and from the lattice. We also find that the data prefer a transverse wavefunction with enhanced end-point contributions.