Systematic uncertainty of offshell corrections and higher-twist contribution in DIS at large x

TL;DR

This paper investigates how theoretical assumptions about higher-twist effects and offshell corrections influence the extraction of the neutron and d-quark structure functions from large-x deep inelastic scattering data, highlighting systematic uncertainties.

Contribution

It provides a systematic analysis of uncertainties and biases from different theoretical models of higher-twist and offshell effects in large-x DIS data analysis.

Findings

Different models of higher-twist corrections significantly affect the extracted PDFs.

Offshell deformations impact the neutron structure function calculations.

Systematic uncertainties are comparable to experimental errors at large x.

Abstract

We study the systematic uncertainty and biases introduced by theoretical assumptions needed to include large-$x$ DIS data in a global QCD analysis. Working in the CTEQ-JLab framework, we focus on different implementations of higher-twist corrections to the nucleon structure functions and of offshell PDF deformations in deuteron targets and discuss how their interplay impacts the extraction of the $d$-quark PDF and the calculation of the neutron structure function at large $x$.