Hyperfine induced transition rates in multiply charged beryllium like ions from storage ring experiments

• Applicant: Professor Dr. Stefan Schippers
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2011 to 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 192993699

Atoms and ions in metastable excited states with very small electromagnetic transition rates are promising systems for energy storage, for realizing ultraprecise atomic clocks, for the diagnostic of astrophysical media regarding the competition of radiative and non-radiative processes, for realizing novel types of cold atomic gases, and for probing fundamental correlation effects in the bound states of few-electron systems. In particular, extremely long lived atomic states such as the lowest excited state in beryllium-like ions, i.e, the 1s2 2s 2p 3P0 state which cannot decay via a one-photon transition, are highly sensitive to correlations within the atomic shell and even to the atoms nuclear structure. If the nucleus has nonzero magnetic moment it can quench the 3P0 state by hyperfine mixing with its neighboring 3P1 state. Recent theoretical calculations which address this effect in multiply charged beryllium like ions disagree significantly with the so far only experimental result. The proposed work will provide accurate experimental values for hyperfine induced transition rates of berylliumlike neon, silicon and sulfur ions in order to significantly enlarge the body of experimental data. The measurements will be carried out using a heavy-ion storage ring equipped with a high-resolution electron target.

• DFG Programme: Research Grants