The pure rotational spectrum of YbOH

TL;DR

This study measures and analyzes the pure rotational spectrum of YbOH, providing detailed hyperfine parameters that support the existence of a perturbing state and facilitate laser cooling for new physics searches.

Contribution

The paper presents the first detailed rotational spectrum analysis of YbOH, revealing hyperfine parameters and evidence of a perturbing state, advancing its potential for laser cooling applications.

Findings

Hyperfine parameters for YbOH were precisely determined.

Evidence of a perturbing state near the ^2_{1/2} state was found.

Results support YbOH's suitability for laser cooling and fundamental physics experiments.

Abstract

The pure rotational spectrum of YbOH has been recorded and analyzed to produce fine and magnetic hyperfine parameters for the $\tilde{X}^2\Sigma^+$(0,0,0) state. These parameters are compared with those determined from the optical study [Melville and Coxon, J. Chem. Phys. 115, 6974-6978 (2001)] and with the values for YbF [Dickinson et al. 115, 6979-6989 (2001)]. The results support the existence of an unobserved perturbing state near the $\tilde{A}^2\Pi_{1/2}$ state, similar to that previously found in YbF. The precisely determined parameters lay the foundation for laser cooling YbOH, which will aid in the search for new physics beyond the standard model.