Nucleon Spin with and without Hyperon Data: A New Tool for Analysis

TL;DR

This paper explores methods to analyze proton spin structure using hyperon decay data and nucleon magnetic moments, clarifying the role of symmetry breaking and comparing different approaches for consistency.

Contribution

It introduces a simplified explanation of hyperon decay data's role in proton spin analysis and compares it with nucleon magnetic moment data, highlighting their near equivalence.

Findings

Hyperon decay data and nucleon magnetic moments yield nearly identical results.

Symmetry breaking clarifies the physics behind hyperon decay analysis.

Models explaining the Gottfried sum rule violation may conflict with SU(3) predictions.

Abstract

We present a simple explanation of the underlying physics in the use of hyperon decay data to obtain information about proton spin structure. We also present an alternative input using nucleon magnetic moment data and show that the results from the two approaches are nearly identical. The role of symmetry breaking is clarified while pointing out that simple models explaining the violation of the Gottfried sum rule via pion emission tend to lose the good SU(3) predictions from Cabibbo theory for hyperon decays.