Year: 2019
Type: article
Abstract: Using resonant two-step laser excitation of trapped $^{232}{\mathrm{Th}}^{+}$ ions, we observe 166 previously unknown energy levels of even parity within the energy range from 7.8 to 9.8 eV and angular momenta from $J=1/2$ to $7/2$. We also classify the high-lying levels observed in our earlier experiments by the total angular momentum and perform multiconfiguration Dirac-Fock calculations to compare their results with the observed level density. The observed levels can be relevant for the excitation or decay of the $^{229m}\mathrm{Th}$ isomeric nuclear state which lies in this energy range. The high density of electronic levels promises a strongly enhanced electronic bridge excitation of the isomer in $^{229}{\mathrm{Th}}^{+}$.
Source: Physical Review A
Language: Latvian
Topic: Atomic and Molecular Physics
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Awards: G4724398935, G6023130887
OpenAlex ID: W2917469342