RFQ
RFQs have been developed at NTG for a wide variety of applications. The 4-rod structure invented by Prof. Dr. A. Schempp was chosen frequently and with great success for example as a compact replacement for very large high voltage injection systems (Cockroft Walton). In the field of medical application this structure appears in the form of an integrated RFQ-Drifttube combination, which became a substantial part of a treatment facility for Cancer-Therapy for example in the new Klinikum in Heidelberg.
The most oustanding advantages of the 4-rod structur in comparison to the 4-vane alternative are:
1. Significantly reduced manufacture costs.
2. Simple tuning concept by means of movable tuning plates.
3. Easy for maintenance and servicing. For example electrodes can be easily replaced as separate parts.
Most recent efforts are taken to develop high power RFQs providing high intensity ion beams for e.g. neutron production and in the field of basic research. Intense neutron spallation sources for material research (IFMIF) require powerful primary driver beams. An interesting application yields the possibility of nuclear waste transmutation in significantly less problematic products (MYRRHA). – The SARAF-CW-RFQ is our first approach to get to such high power levels. Stabel long term CW-operation has been reached for proton operation up to a power level of 40 kW/m corresponding to 50 kV electrode voltage.
Some new developments have been introduced with the most recent FRANZ CW RFQ for the IAP. Among others:
– More efficient cooling system
– Aluminum tank for better heat conductivity
– Improved rf-shieding of feedthroughs
– Enhanced manufacturing precision provides more efficiency (shunt impedance)
– Easy overall access for service and maintenance.
First low level rf-measurements on a 4-stem model can be found here. They show a significant improvement of the efficiency (shunt impedance).
RFQ accelerator are our specialty. If you intend to accelerate ions up to 4 MeV, please consult us. We also gladly provide competent advice regarding beam dynamics and rf-design. mailto: a.bechtold@ntg.de
