Solid targets system with in-situ target dissolution
William Gelbart
ASD Inc.
Poster
The Author claims no conflicts of interest.
In solid targets irradiation systems, the solid target must be transferred to the irradiation position for irradiation and then removed for processing. In the simplest form each target is transferred manually between the hot-cell and the accelerator. More sophisticated systems are using some form of mechanical or pneumatic transfer. Those are not only more complex and expensive, but require large passages to the accelerator vault or target cave, passages that are difficult to add to existing installations and that do create radiation “leaks”.
ASD Inc. has designed and built a self contained unit that is automatically placing the targets in the irradiation position, and at the end of irradiation transfers them to an integral dissolution cell placed at the target station itself. Fresh targets – up to 10 or more – are contained in a detachable cassette that can be easily and quickly replaced once all the targets are irradiated and processed. In most cyclotron installations the cassette change can coincide with the regular maintenance shutdown.
The advantage of this approach is that only the dissolution liquid and the liquid dissolved material are transferred between the target system and the processing hot-cell. The liquids are moved through small diameter tube that is easily routed through existing cable ducts. There is no need for a large, dedicated passages for the pneumatic transfer pipes (in the case of pneumatically transferred targets) and no need for a large hot-cell to house the target receiver. And there is no need for a frequent access to change or collect targets, as is the case in a manual target systems.
The whole system is small with a footprint of only 350mm x 200mm and 240mm vertical clearance. A variety of solid targets can be used with beam power dissipation capabilities up 6 KW. The system requires a supply of cooling water and compressed air. Control of the process can be done by a small, dedicated PLC or can be integrated with the accelerator controls.