Journal Article

Mechanical structure of the nucleon and the baryon octet: twist-2 case

Kim, June-Young, Kim, Hyun-Chul, Won, Ho-Yeon

2024

Overview

A bstract We investigate the gravitational form factors (GFFs) of the nucleon and the baryon octet, decomposed into their flavor components, utilizing a pion mean-field approach grounded in the large N c limit of Quantum Chromodynamics (QCD). Our focus is on the contributions from the twist-2 operators to the flavor-triplet and octet GFFs, and we decompose the mass, angular momentum, and D -term form factors of the nucleon into their respective flavors. The strange quark contributions are found to be relatively mild for the mass and angular momentum form factors, while providing significant corrections to the D -term form factor. In the course of examining the flavor decomposition of the GFFs, we uncover that the effects of twist-4 operators play a crucial role. While the gluonic contributions are suppressed by the packing fraction of the instanton vacuum in the twist-2 case, contributions from twist-4 operators are of order unity, necessitating its explicit consideration.

• Publisher: Springer Berlin Heidelberg,Springer Nature B.V,Springer Nature,SpringerOpen
• Subject: Angular momentum / Asymmetry / Baryons / Classical and Quantum Gravitation / Decomposition / Effective Field Theories of QCD / Elementary Particles / Flavor (particle physics) / Form factors / Fourier transforms / Instantons / Mechanical properties / Nucleons / Operators / Parton Distributions / Physics / Physics and Astronomy / PHYSICS OF ELEMENTARY PARTICLES AND FIELDS / Pions / Properties of Hadrons / Quantum chromodynamics / Quantum Field Theories / Quantum Field Theory / Quantum Physics / Quarks / Regular Article - Theoretical Physics / Relativity Theory / String Theory / Symmetry