Hyperfine interaction with the ${}^{229}$Th nucleus and its low lying isomeric state

Abstract

The thorium nucleus with mass number $A=229$ has attracted much interest because its extremely low lying first excited isomeric state at about $8$eV opens the possibility for the development of a nuclear clock. However, neither the exact energy of this nuclear isomer nor properties, such as nuclear magnetic dipole and electric quadrupole moment are known to a high precision so far. The latter can be determined by investigating the hyperfine structure of thorium atoms or ions. Due to its electronic structure and the long lifetime of the nuclear isomeric state, Th${}^{2+}$ is especially suitable for such kind of studies. In this letter we present a combined experimental and theoretical investigation of the hyperfine structure of the ${}^{229}$Th${}^{2+}$ ion in the nuclear ground and isomeric state. A very good agreement between theory and experiment is found for the nuclear ground state. Moreover, we use our calculations to confirm the recently presented experimental value for the nuclear magnetic dipole moment of the thorium nuclear isomer, which was in contradiction to previous theoretical studies.

References in corpus (10)

• Direct detection of the 229Th nuclear clock transition
• Enhanced effect of temporal variation of the fine structure constant in diatomic molecules
• Development of a configuration-interaction + all-order method for atomic calculations
• Laser spectroscopic characterization of the nuclear clock isomer ${}^{229m}$Th
• Performance of a 229 Thorium solid-state nuclear clock
• Nuclear clocks based on resonant excitation of gamma-transitions
• QED calculation of the 2p3/2-2p1/2 transition energy in five-electron ion of argon
• On Th229 and time-dependent fundamental constants
• Core-valence correlations for atoms with open shells
• Radiative and interelectronic-interaction corrections to the hyperfine splitting in highly charged B-like ions

Cited by in corpus (7)

• The ${}^{229}$Th isomer: prospects for a nuclear optical clock
• Theoretical predictions for the magnetic dipole moment of ${}^{229m}$Th
• Nuclear charge radii of ${}^{229}$Th from isotope and isomer shifts
• ${}^{229m}$Th isomer from a nuclear model perspective
• Excitation of the ${}^{229}$Th nucleus via a two-photon electronic transition
• Shift of nuclear clock transition frequency in ${}^{229}$Th ions due to hyperfine interaction
• Laser Resonance Chromatography of ${}^{229}$Th${}^{3+}$ in He: an ab initio investigation