Collinear laser spectroscopy of atomic cadmium

TL;DR

This study uses collinear laser spectroscopy to measure hyperfine structures of cadmium isotopes, deriving nuclear moments and analyzing hyperfine anomalies, revealing a linear relationship consistent with the Moskowitz-Lombardi rule but with a smaller slope than in mercury.

Contribution

First detailed hyperfine structure analysis of multiple cadmium isotopes, linking experimental data with theoretical calculations to evaluate nuclear moments and hyperfine anomalies.

Findings

Hyperfine structure factors determined for isotopes $^{107-123}$Cd.

Linear hyperfine anomaly relationship observed, smaller slope than in mercury.

Electric field gradient calculated, consistent with ionic transition results.

Abstract

Hyperfine structure $A$ and $B$ factors of the atomic $5s\,5p\,\; ^3\rm{P}_2 \rightarrow 5s\,6s\,\; ^3\rm{S}_1$ transition are determined from collinear laser spectroscopy data of $^{107-123}$Cd and $^{111m-123m}$Cd. Nuclear magnetic moments and electric quadrupole moments are extracted using reference dipole moments and calculated electric field gradients, respectively. The hyperfine structure anomaly for isotopes with $s_{1/2}$ and $d_{5/2}$ nuclear ground states and isomeric $h_{11/2}$ states is evaluated and a linear relationship is observed for all nuclear states except $s_{1/2}$. This corresponds to the Moskowitz-Lombardi rule that was established in the mercury region of the nuclear chart but in the case of cadmium the slope is distinctively smaller than for mercury. In total four atomic and ionic levels were analyzed and all of them exhibit a similar behaviour. The electric field gradient for the atomic $5s\,5p\,\; ^3\mathrm{P}_2$ level is derived from multi-configuration Dirac-Hartree-Fock calculations in order to evaluate the spectroscopic nuclear quadrupole moments. The results are consistent with those obtained in an ionic transition and based on a similar calculation.