ILIMA Project : Towards Pure Isomeric Beams

Although the present experimental program at the SISFRS-ESR facilities has been quite successful and has led to several basic discoveries [1], the field of research is expected to be drastically extended by the next-generation facility FAIR [2]. It will consist of a more powerful driver accelerator, a large acceptance in-flight separator Super-FRS [3], and a new storage-cooler ring system specially adapted to the large phase space and short half-lives of the exotic nuclear beams [4]. Within the FAIR framework, ILIMA [5] is an accepted proposal which will be an extension of the present successful program at the FRS-ESR. One goal is to provide pure isomeric beams circulating in the new storage ring system to be used in reactions with the internal target or collision zones with other stored particles as electrons or antiprotons. An important demonstration of the feasibility in this direction has been achieved in the present experiment by scraping off one component of an isobaric doublet recorded with Schottky Mass Spectrometry [6]. The goal was achieved by a precise mechanical scraper at a dispersive plane in the ESR. This mechanical separation in the micrometer range brought the success as demonstrated in Figure 1. The technique which has been applied is very