Higher Twist Contributions to the Structure Functions F_2^p(x,Q^2) and F_2^d(x,Q^2) at Large x and Higher Orders

TL;DR

This paper investigates higher twist effects in proton and deuteron structure functions at large x, showing that including higher order QCD corrections reduces the estimated higher twist contributions, highlighting the importance of precision in theoretical calculations.

Contribution

It provides a detailed extraction of higher twist contributions at large x across multiple perturbative QCD orders, including NLO to N$^4$LO, demonstrating the impact of higher order corrections.

Findings

Higher twist contributions decrease from NLO to N$^4$LO.

Higher order corrections significantly influence the estimated size of higher twist effects.

The analysis emphasizes the necessity of including higher order terms for accurate structure function modeling.

Abstract

The higher twist contributions to the deeply inelastic structure functions $F_2^{p}(x,Q^2)$ and $F_2^{d}(x,Q^2)$ for larger values of the Bjorken variable $x$ are extracted extrapolating the {twist--2} contributions measured in the large $W^2$ region to the region $4 \GeV^2 \leq W^2 \leq 12.5 \GeV^2$ applying target mass corrections. We compare the results for the NLO, NNLO and N$^3$LO analyzes and include also the large $x$ at N$^4$LO to the Wilson coefficients. A gradual lowering of the higher twist contributions going from NLO to N$^4$LO is observed, which stresses the importance of higher order corrections.