ausblenden:
Schlagwörter:
-
Zusammenfassung:
Hadron beams delivered by normal conducting synchrotrons
are highly attractive in various fundamental
research experiments as well as in the field of tumour
therapy. These applications require fast synchrotron
operation modes with pulse-to-pulse energy variation and
magnetic field slopes up to 10 T/s. The aims are to
optimize the duty-cycle and to minimize treatment times
for the patients as well as to provide extremely stable
properties of the extracted beams, i.e. position and spill
structure. Studies performed at the SIS18 synchrotron at
GSI proved that the ring quadrupoles contribute to the
deterioration of the slowly extracted beam as well as the
dipoles. An attempt has been made to measure the
magnetic fields in the synchrotron magnets with high
precision and speed comparable to the current measurement
with a DCCT used in the power supplies. Adding
magnetic field monitoring into the current control feedback
loop suppresses the unfavourable dynamic effects
from hysteresis and eddy currents. The presentation
describes this approach and the results obtained at the
HIT [1] synchrotron will be discussed.
