Development of a control system for the 14.5 GHz ECR ion source

Abstract

A control system of the 14.5 GHz electron cyclotron resonance (ECR) ion source has been designed and developed in KHIMA(Korea Heavy Ion Medical Accelerator) project which will use C⁶⁺ ions for heavy ion therapy. Production of the selected ion beam in stable operation with safety is a development goal with flexibility by easy access and modification which are necessary during development process with an accelerator. The control system of the ECR ion source system consists of electric control cabinet (ECC) as hardware and main control program (MCP) as software, respectively. ECC developed to manage power and control flow with electric components and controllers controls the injection system, RF system, high voltage & extraction system, analyzing system, vacuum system, cooling system, diagnosis system and safety system. MCP is the supervisory program developed for effective automation and data acquisition by LabVIEW-based graphical programming. The isolated network from a control computer to ECC and bleeder resistors in a steel plate box composed by the simulation result for high voltage power supplies increase reliability and safety. The performance of the developed control system has been verified successfully by beam extraction of C⁴⁺ ion from CO₂ as main gas and He as support gas through an analyzing magnet and a faraday cup with the acquired spectrum at the control system. After optimization with C⁴⁺ ions, measurement of characteristics of C⁶⁺ ions including emittance of the ion beam will be planned early 2013. Also, quantity of C⁶⁺ ions in the same charge to mass ratio will be estimated by using ¹³CO₂ as main gas and He as support gas.