Hannover 2016 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
Q: Fachverband Quantenoptik und Photonik
Q 44: Precision spectroscopy of atoms and ions (with A)
Q 44.10: Poster
Wednesday, March 2, 2016, 16:30–19:00, Empore Lichthof
Towards a nuclear clock based on 229Th: Internal conversion rates for Th ions — •Pavlo Bilous and Adriana Pálffy — Max Planck Institute for Nuclear Physics, Saupfercheckweg 1, D-69117 Heidelberg, Germany
The thorium isotope 229Th bridges atomic and nuclear physics with its unique long-lived nuclear excited state with the energy of 7.8 eV [1]. The advantages of this nuclear transition are its very narrow width, the stability with respect to external perturbations and an accessible frequency within the VUV region, rendering it a candidate for a nuclear clock system. Due to the small excitation energy, typical for outer shell electron transitions, the strongest decay channel of the 7.8 eV nuclear state in a Th atom is internal conversion.
Here we carry out ab initio calculations of internal conversion rates for Th using multi-configurational Dirac-Fock wave functions [2] for the bound atomic electron. We consider internal conversion in atoms and ions with charge states Th+ and Th2+ and several ground and excited state configurations. These results are required for a better understanding of the decay properties of the 229Th clock transition in different materials and experimental setups.
[1] B. R. Beck et al., Phys. Rev. Lett. 98, 142501 (2007).
[2] P. Jönsson et al., Comput. Phys. Commun. 184, 2197 (2013).