Quantitative Study of Geometrical Scaling in Charm Production at HERA

TL;DR

This paper investigates geometrical scaling in charm production at HERA using combined experimental data, testing models with and without charm mass effects, and finds residual scaling improved by including charm mass.

Contribution

The study applies the ratio method to analyze geometrical scaling in charm production, comparing models with and without charm mass effects using recent HERA data.

Findings

Residual geometrical scaling is observed in charm production.

Including charm mass improves the scaling quality.

Both models show some degree of scaling residuals.

Abstract

We apply the method of ratios to search for geometrical scaling in the charm production in deep inelastic scattering. To this end we use recent combined data from H1 and ZEUS experiments. Two forms of geometrical scaling are tested: originally proposed scaling which results from Golec-Biernat-Wusthoff model and scaling motivated by a dipole representation which takes into account charm mass. It turns out that in both cases some residual scaling is present and charm mass inclusion improves scaling quality.