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arXiv · 2608.20146

Exploring chiral dynamics with low-energy electron- and positron-nucleon scattering

C. Weiss
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Abstract

Low-energy lepton-nucleon scattering probes various expressions of the long-distance dynamics in the baryon sector of QCD, governed by chiral symmetry breaking and the $\Delta$ resonance. We discuss some specific studies that could be performed with combined electron- and positron-nucleon scattering at lab energies $E_{e\pm} \lesssim$ 500 MeV. They include: (a) chiral dynamics in the low-$Q^2$ nucleon elastic form factors (peripheral charge and current densities); (b) two-photon exchange effects in the target normal single-spin asymmetry and beam charge asymmetry in elastic and inclusive scattering ($\Delta$ excitation); (c) nucleon generalized polarizabilities in virtual Compton scattering with beam charge asymmetry measurements.

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C. Weiss. 2026-08-20. Exploring chiral dynamics with low-energy electron- and positron-nucleon scattering. https://arxiv.org/abs/2608.20146

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