Excitation of the ${}^{229}$Th nucleus via a two-photon electronic transition

Abstract

We investigate the process of nuclear excitation via a two-photon electron transition (NETP) for the case of the doubly charged thorium. The theory of the NETP process has been devised originally for heavy helium-like ions. In this work, we study this process in the nuclear clock isotope ${}^{229}$Th in the $2+$ charge state. For this purpose, we employ a combination of configuration interaction and many-body perturbation theory to calculate the probability of NETP in resonance approximation. The experimental scenario we propose for the excitation of the low lying isomeric state in ${}^{229}$Th is a circular process starting with a two-step pumping stage followed by NETP. The ideal intermediate steps in this process depend on the supposed energy $\hslash {\omega }_N$ of the nuclear isomeric state. For each of these energies, the best initial state for NETP is calculated. Special focus is put on the most recent experimental results for $\hslash {\omega }_N$.

References in corpus (8)

• Direct detection of the 229Th nuclear clock transition
• Lifetime measurement of the ${}^{229}$Th nuclear isomer
• Excitation of the isomeric ^{229m}Th nuclear state via an electronic bridge process in ^{229}Th^+
• Highly-charged ions for atomic clocks, quantum information, and search for $\alpha$-variation
• Theory of nuclear excitation by electron capture for heavy ions
• A laser excitation scheme for ${}^{229\text{m}}$Th
• Core-valence correlations for atoms with open shells
• Nuclear excitation by two-photon electron transition

Cited by in corpus (8)

• The ${}^{229}$Th isomer: prospects for a nuclear optical clock
• Excitation of ${}^{229m}$Th at Inelastic Scattering of Low Energy Electrons
• Solid-State ${}^{229}\mathrm{Th}$ Nuclear Laser with Two-Photon Pumping
• Internal conversion of the low energy ${}^{229m}$Th isomer in the Thorium anion
• Cross section of the Coulomb excitation of ${}^{229m}$Th by low energy muons
• Proposal for a Nuclear Light Source
• Optical clock based on two-photon spectroscopy of the nuclear transition in ion ${}^{229}$Th in a monochromatic field
• A new scheme for isomer pumping and depletion with high-power lasers