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arXiv · 2412.05050

On the definition of the nucleon axial charge density

J. Yu. Panteleeva·E. Epelbaum·J. Gegelia·U. -G. Meißner
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Abstract

We work out the spatial density distributions corresponding to the axial-vector charge density operator for spin-1/2 systems using states described by sharply localized wave packets in arbitrary Lorentz-frames. The static approximation, leading to the frequently assumed Breit-frame distributions, is also considered. We discuss the interpretation of the resulting spatial densities in terms of the axial charge density.

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J. Yu. Panteleeva, E. Epelbaum, J. Gegelia, U. -G. Meißner. 2024-12-06. On the definition of the nucleon axial charge density. https://arxiv.org/abs/2412.05050

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