Progress in the design and study of a superferric dipole magnet for the GSI fast-pulsed synchrotron SIS100

New experimental results from the investigation of a superferric window frame type dipole magnet with the operating parameters: B=2T, dB/dt=4T/s and pulse repetition rate f=1Hz are presented. The magnet SC coil is made from a hollow multifilamentary NbTi cable, cooled with two-phase helium flow. Special attention is devoted to minimization of AC power losses in the magnet to the specified value of 13W/m. The value of 9W/m has been obtained for a model magnet with the yoke at T=50K. Different possibilities were investigated to reduce the losses in the case of a cold iron yoke (T=4.5K). Other problems, connected with the magnetic field quality, mechanical and cryogenic stability of the magnet under SIS100 operating conditions are also discussed.