Opportunities for negative ions studies at the Frankfurt Low-energy Storage Ring (FLSR)

The room-temperature electrostatic heavy ion storage ring FLSR was originally designed to study the collision dynamics of atoms and molecules. Recently it has been equipped with a RF plasma ion source combined with a charge exchange cell to be able to perform studies with negative ions in the ring. In preliminary experiments beams of He−, O− and OH− could successfully be stored. The measured lifetime of the metastable He−–ion is in good agreement with previous results, showing that the lifetime measurement in this case is not limited by the storage time due to collisional detachment. In the case of O− and OH− storage times in the order of seconds have been achieved. In a next step laser beams will be introduced in the ring allowing photodetachment studies of vibrationally cold molecules.