Nucleon helicity generalized parton distribution at physical pion mass from lattice QCD

The generalized parton distributions (GPDs) offer a window on three-dimensional imaging of the nucleon, providing understanding of how the fundamental properties of the nucleon, such as its mass and spin, arise from the underlying quark and gluon degrees of freedom. In this work, we present the first lattice calculation of the nucleon isovector helicity GPD at physical pion mass, using an a approximate to 0.09 fm lattice ensemble with 2+1+1 flavors of highly improved staggered quarks generated by MILC Collaboration. We perform the GPD calculation in Breit frame using averaged nucleon boost momentum P-z approximate to 2.2 GeV with nonzero momentum transfers in [0.2, 1.0] GeV2. Nonperturbative renormalization in RI/MOM scheme is used to obtain the quasi-distribution before matching to the lightcone GPDs. The three-dimensional distribution (H) over tilde (x, Q(2)) is presented, along with the three-dimensional nucleon tomography and impact-parameter-dependent distribution for selected Bjorken x at mu = 3 GeV in (MS) over bar scheme. (C) 2021 The Author(s). Published by Elsevier B.V.

Automated summary

In this study, the first lattice calculation of the nucleon isovector helicity generalized parton distributions (GPDs) at physical pion mass is presented. These calculations provide insights into the fundamental properties of the nucleon, such as its mass and spin, which arise from the underlying quark and gluon degrees of freedom.