The extraction of 229Th3+ from a buffer-gas stopping cell

TL;DR

This paper demonstrates the direct extraction of triply-charged $^{229}$Th ions from a buffer-gas stopping cell, facilitating nuclear frequency standards and simplifying ion cooling and purification processes.

Contribution

It introduces a novel method for extracting $^{229}$Th$^{3+}$ ions directly from a buffer-gas stopping cell, aiding nuclear transition studies.

Findings

Successful extraction of $^{229}$Th$^{3+}$ ions.

Potential for improved thorium ion cooling and purification.

Advancement in identifying nuclear transitions in $^{229}$Th.

Abstract

In the whole landscape of atomic nuclei, $^{229}$Th is currently the only known nucleus which could allow for the development of a nuclear-based frequency standard, as it possesses an isomeric state of just 7.6 eV energy above the ground state. The 3+ charge state is of special importance in this context, as Th$^{3+}$ allows for a simple laser-cooling scheme. Here we emphasize the direct extraction of triply-charged $^{229}$Th from a buffer-gas stopping cell. This finding will not only simplify any future approach of $^{229}$Th ion cooling, but is also used for thorium-beam purification and in this way provides a powerful tool for the direct identification of the $^{229}$Th isomer to ground state nuclear transition.