Frédéric Genin

Technical status of the first industrial unit of the 10 MeV, 100 kW Rhodotron

The Rhodotron is a new type of industrial electron accelerator developed by IBA, Belgium, on the basis of the pioneering work performed by a French team at CEA, Saclay. The operating principle of this new technology makes it possible to easily produce high energy and high power electron beams. The combination of high energy and high current allows high product throughputs and/or the irradiation of thick structures in the electron mode. An X-ray target is also developed in such a way that the Rhodotron can also be operated in the X-ray mode while maintaining high dose rates. The construction of the first industrial unit (10 MeV, 100 kW) began in January 1992 and the first beam was obtained on October 29, 1993. This machine has now been tested at its full specifications. Technical performance data are presented in this paper.

The use of dose and charge distributions in electron beam processing

Absorbed dose distributions in products treated with energetic electrons are influenced by the electron energy, the atomic composition of the material. the size and shape of the product and its orientation to the electron beam. Dose distributions can be measured by placing small dosimeters at various positions within some products, but more detailed data can be calculated with Monte Carlo codes that are readily available. For high-dose treatment processes, the magnitude and internal distribution of electrostatic charges may be significant. The accumulation of high charges could cause discharges through some materials, which could damage the products. This effect can be avoided by using electrons with sufficiently high energy, so that most of them will pass through the material. Charge distributions are difficult to measure, but they can be calculated with the Monte Carlo method. Dose and charge distributions with a wide range of electron energies in typical materials are presented in this paper. These have been obtained with the Integrated Tiger Series of Coupled Electron/Photon Monte Carlo Transport Codes (ITS). The data illustrate the effects of electron energy and material composition. These quantitative results will enable users to determine the electron energy beam current and beam power requirements for a variety of electron beam treatment processes

The Rhodotron, a New High-energy, High-power, Cw Electron-accelerator

Over the last years, a new kind of industrial electron accelerator has been conjointly developed by the French Atomic Energy Agency (CEA) and IBA (Ion Beam Applications) in Belgium. This accelerator, called the Rhodotron, is a recirculating accelerator, operated in CW. It uses low frequencies (metric waves), that make possible the generation of continuous high-energy high-power beams. The construction of the first industrial model of the Rhodotron began in January 1992. It is a 10 MeV, 100 kW beam power unit, with an additional beam exit at 5 MeV. A target is also being developed in order to allow an efficient conversion of the electrons into X-rays. The different subsystems of this machine are now being assembled and tested. The first beam tests are scheduled for the autumn of 1993. A complete report presenting the state of development of this prototype is included in this paper.