J.L. Bol

Construction of the louvain-la-neuve 30 MeV 500 μA H− cyclotron*

The prototype of a new design of a 30 MeV H − cyclotron for isotope production is in construction in Louvain-la-Neuve (Belgium). The original magnet design combines the advantages of compact and separated sector cyclotrons and requires less than 7 kW of electrical power. The ions are produced in an external multicusp ion source biased at 30 kV, and injected axially. The two 30° dees, supported on half-wavelength vertical resonators are connected at the center. The rf frequency is 65 MHz, and the power for 50 kV dee voltage is 5 kW for one cavity. The cyclotron operation will be fully automatic, using a high-level programmable controller. The magnetic field shimming is completed. Vacuum and rf tests are underway. The first beams are expected at the end of 1986.

High intensity H/sup -/ cyclotrons for radioisotope production

A description is given of Cyclone 30, a 30-MeV, H/sup -/ cyclotron for radioscope production, designed for extremely high extracted beam intensity (500 mu A) and low power consumption (less than 100 kW with a 15-kW extracted beam). The Cyclone 30 prototype has now been operational for years at Louvain-La-Neuve and has achieved all design goals while demonstrating very high reliability. The major events in its development are reviewed. The data gathered so far give general basic trends for future designs; a 70-MeV, 2-mA machine design study is presented.<<ETX>>

A new design of truly selfshielding baby-cyclotrons for positron emitter production

The successful design of the Cyclone 30, a 30-MeV H/sup -/ cyclotron, gave birth to an original design of truly selfshielding baby-cyclotrons dedicated to positron emitter production. This new negative ion cyclotron will deliver 10-MeV protons and 5-MeV deuterons. Up to eight targets are located inside the circular return yoke of the magnet, which serves as a primary neutron and gamma-ray shield. The cyclotron is embedded in an additional neutron shield made of borated-hydrogenated material. One of the main goals of the design is the ease of access to the targets and to the cyclotron inner parts without compromising the shielding efficiency. Any combination of two opposed targets can be irradiated simultaneously. The size and weight of the proposed system are considerably reduced compared to those of existing cyclotrons.<<ETX>>

Operational Results and Development of the E.C.R. Sources and the Injector into Cyclone

A large superconducting ECR-source (ECREVIS) has been producing high charge state ions up to Xe27+ for injection into CYCLONE and as a stand alone source for atomic physics for over two years now. An improved analysing system has been installed increasing greatly the acceptance without harming the resolution. Operational results of transmission and realistic charge state distributions are reported. The design of a more compact ECR-source, to be called OCTOPUS and using water cooled copper solenoids, an open permanent magnet octupole structure and an iron yoke is presented. This source will replace ECREVIS and it is expected to have better performance and to be more reliable and economical to operate.

Operating experience with a 30 MeV, 500 μA H− cyclotron

The prototype of a new design of H− cyclotron for radioisotope production has been built in Louvain-la-Neuve (Belgium). After a brief description of the main design features, the paper describes the beam developments conducted since November 1986. After solving “vacuum runaway” and rf instabilities problems, extracted beam intensities up to 530 μA have been achieved with the prototype. Low power consumption, high energy conversion efficiency, high reliability, automatic operation and low activation level have also been demonstrated on this prototype.