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arXiv · 2406.00653

Study of the alpha-particle monopole transition form factor

M. Viviani·A. Kievsky·L. E. Marcucci·L. Girlanda
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Abstract

The 4He monopole form factor is studied by computing the transition matrix element of the electromagnetic charge operator between the 4He ground-state and the p+3H and n+3He scattering states. The nuclear wave functions are calculated using the hyperspherical harmonic method, by starting from Hamiltonians including two- and three-body forces derived in chiral effective field theory. The electromagnetic charge operator retains, beyond the leading order (impulse approximation) term, also higher order contributions, as relativistic corrections and meson-exchange currents. The results for the monopole form factor are in fairly agreement with recent MAMI data. Comparison with other theoretical calculations are also provided.

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M. Viviani, A. Kievsky, L. E. Marcucci, L. Girlanda. 2024-06-02. Study of the alpha-particle monopole transition form factor. https://arxiv.org/abs/2406.00653

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