AP-Sonderseminar: Highly charged ions: clock with 19 digits precision, enhanced effects of variation of fine structure constant, quantum chaos and enhancement of electron recombination

We have shown that some ions have narrow optical transitions suitable for making atomic clock with accuracy 10^-19 (similar to 229Th nuclear clock). Effects of temporal variation of the fundamental constants may be 25 times larger than in singly charged ions and neutral atoms. We developed a statistical theory for the resonant multi-electron recombination based on properties of chaotic eigenstates [1]. Level density of many-body states exponentially increases with the number of excited electrons. When the residual electron-electron interaction exceeds the interval between these levels, the eigenstates become ”chaotic” superposition of a large number of Hartree-Fock determinant basis states. This situation takes place in some rare-earth atoms and majority of multiply-charged ions excited by the electron recombination. We derived a formula for the resonant multi-electron recombination via di-electron doorway states leading to such compound resonances and performed numerical calculations for the electron recombination with tungsten ions W^q+, q = 17 - 24. A recent experiment [2] showed that the electron recombination of tungsten ion W²⁰⁺ exceeds the theoretical direct recombination by three order of magnitude. Our calculations agree with this experimental result. References: [1] V. V. Flambaum, A. A. Gribakina, G. F. Gribakin, and C. Harabati, Electron recombination with multicharged ions via chaotic many-electron states, Phys. Rev. A 60, pp. 012713-7 (2002); arxiv: 1204.3707 [2] S. Schippers et al., Dielectronic recombination of xenonlike tungsten ions, Phys. Rev. A 83, pp. 012711-6 (2011).