Detecting bubbles in exotic nuclei

TL;DR

This paper investigates the formation of proton bubbles in neutron-rich Argon isotopes, emphasizing the role of pairing effects and advocating for experimental measurements with upcoming electron scattering facilities.

Contribution

It identifies conditions under which proton bubbles can form in neutron-rich argon isotopes and assesses pairing effects that influence bubble stability.

Findings

Proton bubbles are likely in very neutron-rich argon isotopes like $^{68}$Ar.

Pairing effects do not prevent bubble formation in these isotopes.

Future electron scattering experiments are crucial for measuring charge density distributions.

Abstract

The occurrence of a bubble, due to an inversion of s$_{1/2}$ state with the state usually located above, is investigated. Proton bubbles in neutron-rich Argon isotopes are optimal candidates. Pairing effects which can play against the bubble formation are evaluated. They cannot prevent bubble formation in very neutron-rich argon isotopes such as $^{68}$Ar. This pleads for a measurement of the charge density of neutron-rich argon isotopes in the forthcoming years, with the advent of electron scattering experiments in next generation exotic beam facilities such as FAIR or RIBF.