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arXiv · 2510.09140

Indirect method for nuclear reactions and the role of the self energy

Gregory Potel
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Abstract

When a nuclear species (e.g., a nucleon or a deuteron nucleus) propagating freely is made to collide with a target nucleus, its trajectory is modified by exchanging variable amounts of energy, mass, linear and angular momentum with the target, according to its interaction with the nuclear medium. By addressing this perturbation away from the free path, one hopes to learn something about the nature of the medium through which our probe propagates. This is the essence of the experimental use of nuclear reactions for the purpose of gathering information about nuclear structure. In order to deal with the structure and the reaction aspects of a specific experiment on the same footing, it is therefore desirable to identify a theoretical construct that embodies the modification of the propagation of a particle in the medium with respect to the free case, and use it both for the determination of the nuclear spectrum (structure) and for the calculation of scattering observables (reaction). A candidate for such an object is the self energy, and we will try in the present lectures to put it at the center stage in the formulation of scattering theory.

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Gregory Potel. 2025-11-06. Indirect method for nuclear reactions and the role of the self energy. https://arxiv.org/abs/2510.09140

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