• S. Sorge
  GSI, Darmstadt

The SIS-100 heavy ion synchrotron will play a key role within the future FAIR project underway at GSI. Although it is optimized for fast extraction, also slow extraction will be used. Slow extraction is based on the excitation of a third order resonance leading to the formation of a stable triangular phase space area. During the extraction process, particles leave this area along separatrices, where they pass the blade of the electro-static septum under a certain angle. Even in a low current regime the spread in the particle momenta leads to a spread in this angle which causes particle loss, in particular, at the blade of the electro-static septum. As a consequence the septum blade as well as the subsequent magnets will be irradiated. At high beam intensities space charge or electron clouds cause an additional tune spread which could increase the particle loss. In our study we model the extraction process and estimate the losses for high beam intensities.