Scattering lengths beyond the nuclear scale and the Efimov effect

TL;DR

This paper explores the possibility of observing the Efimov effect in nuclear systems by examining neutron-nucleus interactions with extremely large scattering lengths, focusing on the $^{17}$B-$n$ system.

Contribution

It investigates the potential for nuclear systems to exhibit Efimov physics due to large scattering lengths, extending the phenomenon beyond atomic systems.

Findings

Large scattering lengths may enable Efimov states in nuclei.

Analysis of $^{17}$B-$n$ system suggests possible Efimov trimer formation.

Implications for nuclear structure and universal phenomena are discussed.

Abstract

The interaction of neutrons and nuclei at low energies may potentially lead to scattering lengths several orders of magnitude larger than the effective range of the interaction, well beyond the nuclear scale. If such cases existed, they could lead to the observation of the Efimov effect in nuclei, a remarkable universal phenomenon that has been observed only in atoms. The interaction parameters of neutrons scattering off unstable nuclei can be explored in neutron-nucleus systems created after the fast removal of a few nucleons from a slightly heavier beam. The case of the $^{17}$B-$n$ system is considered, and the implications of its potentially huge scattering length on the structure of $^{19}$B as a $^{17}$B-$n$-$n$ Efimov trimer are discussed.