Study of the magnetic octupole moment of $^{173}$Yb using collinear laser spectroscopy

TL;DR

This study used collinear laser spectroscopy to measure hyperfine constants in neutral ytterbium-173, aiming to detect its magnetic octupole moment, but found no significant evidence for it.

Contribution

First high-resolution measurement of hyperfine constants in Yb-173 using collinear laser spectroscopy across multiple transitions.

Findings

No significant magnetic octupole moment detected in Yb-173

High-resolution hyperfine constants obtained for three transitions

Method demonstrates effective probing of metastable states

Abstract

The hyperfine constants of the $^3$P$^{\circ}_2$ state in neutral Yb have been measured using three different dipole transitions. This state was recently shown to have a comparatively large hyperfine magnetic octupole splitting, and thus a puzzlingly large magnetic octupole moment. The measurement is performed using collinear laser spectroscopy on a fast atomic beam, which provides a straightforward route to probing long-lived metastable atomic states with high resolution. From the combined analysis of all three lines we find no significant evidence for a non-zero octupole moment in $^{173}$Yb.