Learning from knockout reactions using a dispersive optical model

M. C. Atkinson; W. H. Dickhoff

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arXiv · 2410.09287

Learning from knockout reactions using a dispersive optical model

M. C. Atkinson·W. H. Dickhoff

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Abstract

We present the empirical dispersive optical model (DOM) as applied to direct nuclear reactions. The DOM links both scattering and bound-state experimental data through a dispersion relation which allows for fully-consistent, data-informed predictions for nuclei where such data exists. In particular, we review investigations of the electron-induced proton knockout reaction from both $^{40}$Ca and $^{48}$Ca in a distorted-wave impulse approximation (DWIA) utilizing the DOM for a fully-consistent description. Viewing these reactions through the lens of the DOM allows us to connect the documented quenching of spectroscopic factors with increased high-momentum proton content in neutron-rich nuclei. A similar DOM-DWIA description of the proton-induced knockout from $^{40}$Ca, however, does not currently fit in the consistent story of its electron-induced counterpart. With the main difference in the proton-induced case being the use of an effective proton-proton interaction, we suggest that a more sophisticated in-medium interaction would lead to consistent results.

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M. C. Atkinson, W. H. Dickhoff. 2024-10-11. Learning from knockout reactions using a dispersive optical model. https://arxiv.org/abs/2410.09287

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