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arXiv · hep-ph/0108015

Delocalization of the axial charge in the chiral limit

R. L. Jaffe
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Abstract

The nucleon's axial vector charge, g_A, becomes delocalized in the chiral limit. When m_π= 0, and SU(2)_L x SU(2)_R is exact, 1/3 of the nucleon's axial charge is to be found at infinite distance from the nucleon. For finite m_πthis result is approached smoothly as m_π-> 0. We illustrate this effect by considering the lepton-proton spin-spin interaction arising from Z^0 exchange as a function of m_π. Delocalization may have implications for lattice calculations of g_A and in nuclei.

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R. L. Jaffe. 2002-01-03. Delocalization of the axial charge in the chiral limit. https://doi.org/10.1016/s0370-2693(02)01242-x

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