Including heavy quark production in ZEUS-PDF fits

TL;DR

This paper explores incorporating heavy quark production data into ZEUS parton distribution function fits, examining different schemes and approaches to improve the understanding of heavy quark contributions at HERA.

Contribution

It introduces a method to include heavy quark data in PDF fits by extending the DGLAP formalism and compares various heavy flavour schemes and alpha_s running approaches.

Findings

Heavy quarks can contribute up to 30% of F2 at HERA.

Different heavy flavour schemes impact the PDF fits.

Approaches to alpha_s running affect the results.

Abstract

At HERA heavy quarks may contribute up to 30% of the structure function $F_2$. The potential of including heavy-quark data in the ZEUS PDF fits is explored, using $D^*$ double differential cross-sections as well as the inclusive quantities $F_2^{c\bar{c}}$, $F_2^{c\bar{c}}$. The introduction of heavy quarks requires an extension of the DGLAP formalism. The effect of using different heavy flavour number schemes, and different approaches to the running of $\alpha_s$, are compared.