1998/08/31 by Pervez Hoodbhoy, Xiangdong Ji, Wei Lu +1 · 2 citations
Physics and Astronomy · #High-Energy Particle Collisions Research #Particle physics theoretical and experimental studies #Quantum Chromodynamics and Particle Interactions #hep-ph
paper · pdf · doi:10.1103/physrevd.59.074010
published as Phys.Rev. D59 (1999) 074010 · Minor corrections are made in the text
arxiv created 1998/09/03 · openalex publication_date 1999/02/26 · arxiv updated 2009/11/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We study the chromodynamical gauge symmetry in relation to the internal spin structure of the nucleon. We show that (1) even in the helicity eigenstates the gauge-dependent spin and orbital angular momentum operators do not have gauge-independent matrix element, (2) the evolution equations for the gluon spin take very different forms in the Feynman and axial gauges, but yield the same leading behavior in the asymptotic limit, and (3) the complete evolution of the gauge-dependent orbital angular momenta appears intractable in the light-cone gauge. We define a new gluon orbital angular momentum distribution Lg(x) which is an experimental observable and has a simple scale evolution. However, its physical interpretation makes sense only in the light-cone gauge just like the gluon helicity distribution \ensuremathΔg(x).