Measurement of hyperfine structure and isotope shifts in the Dy 421-nm transition

TL;DR

This study measures hyperfine coefficients and isotope shifts in the dysprosium 421-nm transition using laser spectroscopy, providing data crucial for laser cooling and fundamental constant variation experiments.

Contribution

It presents the first detailed measurement of hyperfine and isotope shifts for this transition, confirming the excited state's configuration and applying King Plot analysis.

Findings

Determined hyperfine coefficients and isotope shifts for Dy I 421-nm transition.

Confirmed the pure $4f^{10}6s6p$ configuration of the excited state.

Performed King Plot analysis to extract the specific mass shift.

Abstract

A measurement of the hyperfine coefficients and isotope shifts for the Dy I 421.291 nm transition [$4f^{10}6s^2 (J=8)\to4f^{10}6s6p (J=9)$] using atomic beam laser-induced fluorescence spectroscopy is presented. A King Plot analysis is performed to determine a specific mass shift of $\delta \nu_{sms}^{164-162}=11(7)$ Hz for the 421-nm transition, confirming the pure $4f^{10}6s6p$ configuration of the excited state. This transition is currently being explored for laser cooling of an atomic beam of dysprosium used in a search for a temporal variation of the fine-structure constant.