Towards high-precision parton distributions from lattice QCD via distillation

Journal of High Energy Physics

Savvas Zafeiropoulos¹  Kostas Orginos²  Colin Egerer²  Eloy Romero³  Robert G. Edwards³  David G. Richards³  Christos Kallidonis³  Anatoly V. Radyushkin⁴ 

[1] Aix Marseille Univ, Université de Toulon, CNRS, CPT, Marseille, France;Department of Physics, William and Mary, 300 Ukrop Way, 23187, Williamsburg, Virginia, USA;Thomas Jefferson National Accelerator Facility, 12000 Jefferson ave., 23606, Newport News, VA, USA;Thomas Jefferson National Accelerator Facility, 12000 Jefferson ave., 23606, Newport News, VA, USA;Thomas Jefferson National Accelerator Facility, 12000 Jefferson ave., 23606, Newport News, VA, USA;Physics Department, Old Dominion University, 4600 Elkhorn Ave., 23529, Norfolk, VA, USA;

关键词: Lattice field theory simulation;    QCD Phenomenology;   

DOI  :  10.1007/JHEP11(2021)148

来源: Springer

【 摘 要 】

We apply the Distillation spatial smearing program to the extraction of the unpolarized isovector valence PDF of the nucleon. The improved volume sampling and control of excited-states afforded by distillation leads to a dramatically improved determination of the requisite Ioffe-time Pseudo-distribution (pITD). The impact of higher-twist effects is subsequently explored by extending the Wilson line length present in our non-local operators to one half the spatial extent of the lattice ensemble considered. The valence PDF is extracted by analyzing both the matched Ioffe-time Distribution (ITD), as well as a direct matching of the pITD to the PDF. Through development of a novel prescription to obtain the PDF from the pITD, we establish a concerning deviation of the pITD from the expected DGLAP evolution of the pseudo-PDF. The presence of DGLAP evolution is observed once more following introduction of a discretization term into the PDF extractions. Observance and correction of this discrepancy further highlights the utility of distillation in such structure studies.

【 授权许可】

CC BY