High-precision mass measurements for fundamental studies with a four-trap mass spectrometer

• Applicant: Professor Dr. Klaus Blaum
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: from 2007 to 2012
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 50377722

A novel four-trap system consisting of one monitoring trap, two preparation traps and one measurement trap will be developed and operated. This Penning trap system will be located inside a superconducting magnet with one homogeneous field zone for precision mass measurements on highly charged stable and long-lived ions. The preparation traps allow for the preparation of the reference ion and the ion of interest prior to their transport to the precision trap, where the actual mass measurement takes place. The highly charged ion in the monitoring trap allows for the in-situ calibration and monitoring of the magnetic field stability. The measurements on single ions and the permanent exchange of the ions in the precision trap allow minimizing ion-ion interactions as well as uncertainties due to magnetic field fluctuations. Furthermore, a direct mass difference measurement is possible. It is intended to perform mass measurements with relative uncertainties of <10-11, which corresponds to a mass uncertainty of δm ≈ 2 eV for 238U. This would allow one, e.g., to measure the binding energy of highly charged uranium with none 238U92+ or one electron 238U91+ better than presently achieved by X-ray spectroscopy. A stringent test of quantum electrodynamics and of electron correlations in the little explored regime of extreme electromagnetic fields can be performed.

• DFG Programme: Research Grants
• Major Instrumentation: superconducting magnet
• Instrumentation Group: 0120 Supraleitende Labormagnete