Laser Photodetachment Studies on negative Ions in the Frankfurt Low-Energy Storage Ring (FLSR)ONLINE ONLY

The Frankfurt Low-energy Storage Ring (FLSR) is a room temperature electrostatic storage ring, which can reduce the internal energy of stored ions almost to the ambient temperature, being suitable for laser photodetachment threshold (LPT) spectroscopy to determine the electron affinity of negatively charged ions. The latter play a key role in accelerator mass spectrometry (AMS): lasers can selectively neutralize undesired isobars, providing a purified beam of an isotope of interest. To extend the range of available AMS nuclides, it is necessary to identify neutralization schemes for unwanted atomic and molecular negative ions.

To achieve this goal, a source for negative ions was installed at FLSR and a compact laser lab was constructed guiding laser beams into FLSR. The laser setup is based on a tunable Ti:Sapphire laser pumped by a high repetition Nd:YAG laser. The neutralized ions are further downstream detected by a position sensitive MCP detector.

An overview of the setup and first results of precision spectroscopy of O− will be presented. An outlook of further LPT studies will be given.