Understanding the proton's spin structure

Abstract

We discuss the tremendous progress that has been towards an understanding of how the spin of the proton is distributed on its quark and gluon constituents. This is a problem that began in earnest twenty years ago with the discovery of the proton ``spin crisis'' by the European Muon Collaboration. The discoveries prompted by that original work have given us unprecedented insight into the amount of spin carried by polarized gluons and the orbital angular momentum of the quarks.

Review article for J. Phys. G, 1 figure, 22 pages

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Cited by in corpus (21)

• The Spin Structure of the Nucleon
• Colliding particles carrying non-zero orbital angular momentum
• Sketching the pion's valence-quark generalised parton distribution
• The Quark and Gluon Structure of the Proton
• Generalised parton distributions from the off-forward Compton amplitude in lattice QCD
• Spin and angular momentum in the nucleon
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• The spin of the proton in chiral effective field theory
• Art of spin decomposition
• Transverse Momentum and Transverse Momentum Distributions in the MIT Bag Model
• Proton spin in leading order of the covariant approach
• High-energy physics with particles carrying non-zero orbital angular momentum
• DSE inspired model for the pion's valence dressed-quark GPD
• Reflections on Chiral Symmetry within QCD
• Orbital Angular Momentum in Scalar Diquark Model and QED
• Re-examining valence quark spin distributions
• Gauge invariant gluon spin operator for spinless non-linear wave solutions
• Scaling Transformation for Nonlocal Interactions
• Helicity dependent parton distributions
• On the role of quark orbital angular momentum in the proton spin
• Renormalization Group Running of the Parity Operator in Lorentz-Violating Quantum Field Theory