10 MV FN-Tandem

10 MV FN-Tandem AMS unit

Ion source
10 MV FN-Tandem accelerator

The Cologne FN-Tandem accelerator can generate voltages of up to 10 million volts. The facility therefore supplies ion beams with the highest energies for AMS measurements in Europe.
Beam guidance

After passing through a 90° magnet, the atoms pass through various ion-optical elements in order to filter out the isotopes of interest.
Gas-filled magnet

The Kölnder 10 MV AMS unit has a magnet that can be filled with gases at low pressures. This makes it easier to separate the isotopes of interest from the neighboring isotopes, in particular the so-called isobars.
Everything is automatic!

The 10 MV unit can now be controlled and monitored almost fully automatically, which ultimately also improves the measurement results. For example, the system can be used to measure the very rare isotope 60-Fe.

The AMS system at the 10 MV accelerator is dedicated to the detection of medium-heavy radionuclides. It has an achromatic injector with a fast injection system and a high-energy mass spectrometer with a 90° analyzing magnet, behind which the ion currents of the stable nuclides are measured in offset Faraday cups. Isobaric suppression can be carried out via a multi-stage isotope-specific energy loss measurement with combinations of silicon nitride foils, a 30° electrostatic analyser, a 4 m time-of-flight system and a gas ionization detector. In addition, the AMS system was extended by a 135° magnet for the gas-filled mode to increase the transmission for radionuclide measurements such as ⁶⁰Fe.