Ion-Laser Interaction Mass Spectrometry
The AMS group in Dresden explores and develops new methods to filter out isobaric interferences from an ion beam. Ion Laser InterAction Mass Spectrometry (ILIAMS) is such an element-selective filter for negative ion beams. Molecular and atomic anions are slowed down to kinetic energies of few 10 eVs and are guided through a linear Paul-trap, a buffer gas filled radiofrequency quadrupole. The interaction with the buffer gas further slows down the ions. This way, one reaches interaction times of several milliseconds for the ions with photons of a collinearly injected laser beam that neutralizes the isobaric anions via photodetachment of the surplus electron.
At our partner, the group of Isotope Phyics of the Unviersity of Vienna, such a system is already successfully connected to an Accelerator Mass Spectrometer and applied for measurements of the nuclides 26Al, 36Cl and 90Sr in environmental samples. In a collaboration the method is further devoloped for other rare isotopes (e.g. 135Cs, 137Cs, 182Hf) that are of interest in environmental sciences or nuclear astrophysics.
At HZDR we presently further contribute to the improvement of this method by designing and setting up test beam lines for the second generation of an ion cooler.
contact: Johannes Lachner