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arXiv · nucl-th/9906014

Neutron charge radius and the Dirac equation

M. Bawin·S. A. Coon
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Abstract

We consider the Dirac equation for a finite-size neutron in an external electric field. We explicitly incorporate Dirac-Pauli form factors into the Dirac equation. After a non-relativistic reduction, the Darwin-Foldy term is cancelled by a contribution from the Dirac form factor, so that the only coefficient of the external field charge density is $e/6 r^2_{En}$, i. e. the root mean square radius associated with the electric Sachs form factor . Our result is similar to a recent result of Isgur, and reconciles two apparently conflicting viewpoints about the use of the Dirac equation for the description of nucleons.

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M. Bawin, S. A. Coon. 1999-06-05. Neutron charge radius and the Dirac equation. https://doi.org/10.1103/physrevc.60.025207

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