A unified description of diffractive deep inelastic scattering with saturation

TL;DR

This paper introduces a unified, saturation-based dipole model for inclusive diffraction in deep inelastic scattering, accurately describing HERA data with minimal parameters and incorporating heavy-quark effects.

Contribution

It presents a novel saturation model for diffractive DIS that includes heavy-quark contributions and achieves a parameter-free fit to experimental data.

Findings

Saturation scale Q_s(x) exceeds 1 GeV at x=10^{-5}

Model accurately fits HERA diffraction data with chi^2/points=1.2

Incorporates large-Q^2 and small-beta limits in the dipole framework

Abstract

We propose a new description of inclusive diffraction in deep inelastic scattering (DIS). The diffractive structure functions are expressed in the dipole picture and contain heavy-quark contributions. The dipole scattering amplitude, a saturation model fitted on inclusive DIS data, features a saturation scale Q_s(x) larger than 1 GeV for x=10^{-5}. The q\bar{q}g contribution to the diffractive final state is modeled in such a way that both the large-Q^2 and small-beta limits are implemented. In the regime xpom<0.01 in which saturation is expected to be relevant, we obtain a parameter-free description of the HERA data with chi^2/points=1.2.