• E.S. Fischer, J. Macavei, A. Mierau, P. Schnizer, P.J. Spiller, St. Wilfert
  GSI, Darmstadt

The FAIR SIS100 accelerator at GSI Darmstadt will be equipped with fast ramped superconducting magnets. The high current Uranium beam modes with intermediate charge states, require ultra low vacuum pressures that can be achieved in long term operation only by cold beam pipes acting as a cryopump with stable temperatures well below 12 K for all operating cycles. The straightforward layout for reliable cooling usually conflicts with an efficient design for fast ramped superconducting accelerator magnets, strongly affected by AC loss generation, field distortion and mechanical stability problems. A full functional vacuum chamber design for SIS 100 has to take into account all these conflicting boundary conditions and trade off between mechanical stability, acceptable field distortions, AC loss minimisation and achievable temperatures. We discuss the cooling conditions for the dipoles and for the beam pipe including first test results. The analysis of the principal design aspects for the vacuum chamber with respect to the magnets operation parameters and an integral design approach are given. We present a technological feasible solution for model testing and full scale manufacturing.

• P.J. Spiller, U. Blell, L.H.J. Bozyk, H. Eickhoff, E.S. Fischer, E. Floch, F. Hagenbuck, M. Kauschke, A. Krämer, J.P. Meier, C. Mühle, N. Pyka, S. Ratschow, H. Reich-Sprenger, P. Schnitzer, J. Stadlmann, St. Wilfert
  GSI, Darmstadt

The engineering design, including the specifications for the accelerator components of the FAIR synchrotron SIS100 has been summarized in the Technical Design Report. The final stage of technical planning shall approach production readiness for the major technical systems in 2010. Significant progress has been achieved in the design of the cryomagnetic system with its main dipole and quadrupole modules, enabling the production of the first pre-series dipole magnet. Slight modifications of the lattice have been implemented to equalize most of the cryostat interconnections, leading to a simplified design and installation effort, and a reduced variety of components and spar parts. The new parallel tunnel allows optimal short interconnections between the supply units and power converters and the accelerator components. The status of the engineering design of SIS100 will be reported.