# Electric quadrupole channel of the 7.8 eV 229 Th transition

@article{Bilous2018ElectricQC, title={Electric quadrupole channel of the 7.8 eV 229 Th transition}, author={Pavlo V. Bilous and Nikolay Minkov and Adriana P'alffy}, journal={Physical Review C}, year={2018}, volume={97}, pages={044320} }

The unique isomeric transition at 7.8 eV in $~^{229}\mathrm{Th}$ has a magnetic dipole ($M1$) and an electric quadrupole ($E2$) multipole mixing. So far, the $E2$ component has been widely disregarded. Here, we investigate the nuclear physics nature and the impact of the $E2$ decay channel for the nuclear coupling to the atomic shell based on the newest theoretical predictions for the corresponding reduced nuclear transition probabilities. Our results show that the contribution of the $E2…

## 14 Citations

Excitation of the
Th229
nucleus via a two-photon electronic transition

- PhysicsPhysical Review A
- 2019

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…

The $$^{229}$$Th isomer: prospects for a nuclear optical clock

- Physics
- 2020

The proposal for the development of a nuclear optical clock has triggered a multitude of experimental and theoretical studies. In particular the prediction of an unprecedented systematic frequency…

Resonant Electronic-Bridge Excitation of the ^{235}U Nuclear Transition in Ions with Chaotic Spectra.

- PhysicsPhysical review letters
- 2018

A quantum statistical theory based on many-body quantum chaos is presented to demonstrate that typical values for the electronic factor increase the probability of electronic bridge in ^{235}U^{7+} by many orders of magnitude.

Nuclear Excitation of the ^{229}Th Isomer via Defect States in Doped Crystals.

- PhysicsPhysical review letters
- 2020

It is shown that although previously viewed as a nuisance, the defect states provide a starting point for nuclear excitation via electronic bridge mechanisms involving stimulated emission or absorption using an optical laser.

The theory of direct laser excitation of nuclear transitions

- Physics
- 2020

A comprehensive theoretical study of direct laser excitation of a nuclear state based on the density matrix formalism is presented. The nuclear clock isomer $^{229\text{m}}$Th is discussed in detail,…

The thorium-229 low-energy isomer and the nuclear clock

- PhysicsNature Reviews Physics
- 2021

The 229Th nucleus has an isomeric state at an energy of about 8 eV above the ground state, several orders of magnitude lower than typical nuclear excitation energies. This has inspired the…

Electronic Bridge Excitation in Highly Charged ^{229}Th Ions.

- PhysicsPhysical review letters
- 2020

It is shown how to implement a promising electronic bridge scheme in an electron beam ion trap starting from a metastable electronic state to efficiently drive the nuclear transition by coupling it to the electronic shell.

Collective effects in
Th229
-doped crystals

- PhysicsPhysical Review A
- 2018

Vacuum-ultraviolet-transparent crystals have been proposed as host lattice for the coherent driving of the unusually low-lying isomer excitation in $^{229}$Th for metrology and quantum optics…

Driven electronic bridge processes via defect states in
Th229
-doped crystals

- Physics
- 2021

Brenden S. Nickerson, ∗ Martin Pimon, Pavlo V. Bilous, 1 Johannes Gugler, Georgy A. Kazakov, Tomas Sikorsky, Kjeld Beeks, Andreas Grüneis, 2 Thorsten Schumm, and Adriana Pálffy 1, †…

Studies of thorium and ytterbium ion trap loading from laser ablation for gravity monitoring with nuclear clocks

- Physics
- 2020

Compact and robust ion traps for thorium are enabling technology for the next generation of atomic clocks based on a low-energy isomeric transition in the thorium-229 nucleus. We aim at a laser…

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