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The KOMAC facility consists of low-energy components, including a 50-keV ion source, a lowenergy beam transport (LEBT), a 3-MeV radio-frequency quadrupole (RFQ), and a 20-MeV drift tube linac (DTL), as well as high-energy components, including seven DTL tanks for the 100-MeV proton beam. The KOMAC includes ten beam lines, five for 20-MeV beams and five for 100-MeV beams. The peak beam current and the maximum beam duty are 20 mA and 24% for the 20-MeV linac and 20 mA and 8% for the 100-MeV linac, respectively. Four high-voltage convertor modulators are used. Each modulator drives two or three klystrons. The peak output power is 5.8 MW, and the average power is 520 kW with a duty of 9%. The pulse width and repetition rate are 1.5 ms and 60 Hz, respectively.

The beam diagnostics instrument used to measure the beam properties is one of the important devices for the 100-MeV proton linear accelerator of the KOrea Multi-purpose Accelerator Complex (KOMAC). A data acquisition system (DAQ) is required to collect the output beam signals conditioned in the analog front-end circuitry of a beam loss monitor (BLM) and a beam position monitor (BPM). The electrical beam signal must be digitized, and the sampling has to be synchronized to a global timing system that produces a pulse signal for the pulsed beam operation. The digitized data must be accessible by the experimental physics and industrial control system (EPICS)-based control system, which manages all accelerator control. An input output controller (IOC), which runs Linux on a central process unit (CPU) module with a peripheral component interconnect (PCI) express-based Analog-to-digital converter (ADC) card, has been adopted to satisfy the requirements. An associated Linux driver and EPICS device support module have also been developed. The IOC meets the requirements, and the development and maintenance of software for the IOC is very efficient. In this paper, the details of the DAQ system for the BLM and the BPM with the introduction of the KOMAC beam-diagnostics devices, along with the performance, are described.

The 100-MeV proton linear accelerator of the Korea Multi-purpose Accelerator Complex (KOMAC) has been developed. The beam service started this year after performing the beam commissioning. If the very sensitive and essential equipment is to be protected during machine operation, a machine interlock system is required, and the interlock system has been implemented. The purpose of the interlock system is to shut off the beam when the radio-frequency (RF) and ion source are unstable or a beam loss occurs. The interlock signal of the KOMAC linac includes a variety of sources, such as the beam loss, RF and high-voltage converter modulator faults, and fast closing valves of the vacuum window at the beam lines and so on. This system consists of a hardware-based interlock system using analog circuits and a software-based interlock system using an industrial programmable logic controller (PLC). The hardware-based interlock system has been fabricated, and the requirement has been satisfied with the results being within 10 µs. The software logic interlock system using the PLC has been connected to the framework of with the experimental physics and industrial control system (EPICS) to integrate a variety of interlock signals and to control the machine components when an interlock occurs. This paper will describe the design and the construction of the machine interlock system for the KOMAC 100-MeV linac.

The Proton Engineering Frontier Project (PEFP) 20-MeV proton linear accelerator is currently operating at the Korea Atomic Energy Research Institute (KAERI). The ion source of the 100-MeV proton linac needs at least a 100-hour operation time. To meet the goal, we have developed a microwave ion source that uses no filament. For the ion source, a remote control system has been developed by using experimental physics and the industrial control system (EPICS) software framework. The control system consists of a versa module europa (VME) and EPICS-based embedded applications running on a VxWorks real-time operating system. The main purpose of the control system is to control and monitor the operational variables of the components remotely and to protect operators from radiation exposure and the components from critical problems during beam extraction. We successfully performed the operation test of the control system to confirm the degree of safety during the hardware performance.

A 20-MeV proton accelerator has been developed and tested at the Korea Atomic Energy Institute (KAERI) by the Proton Engineering Frontier Project (PEFP). Beam phase was measured at the end of the 20-MeV accelerator by using the beam position monitor (BPM) signal. The beam current and phase were measured by changing the relative RF phase between the 3-MeV radio frequency quadrupole (RFQ) and the 20-MeV drift; tube linac (DTL), and the results were compared with those simulated by using the PARMILA code. In tins paper, the beam phase measurement results are presented, and the phase scan results based on the normal operating condition are compared with the simulation results.

Development of the Resonant-Frequency Monitoring System for the PEFP DTL Young-Gi Song, Han-Sung Kim, Hyeok-Jung Kwon and Yong-Sub Cho Proton Engineering Frontier Project, Korea Atomic Energy Research Institute, Daejeon 305-353 (Received 4 September 2008) A 20-MeV, 20-mA proton linac, which is comprised of a 50-keV proton injector, a 3-MeV radio frequency quadrupole (RFQ) and 20-MeV drift tube linac (DTL), has been developed in the Proton Engineering Frontier Project (PEFP). For a stable and e cient acceleration of a proton beam, the resonant frequency of the DTL cavities should be matched to the high power RF driving frequency. In PEFP DTL, a resonant control cooling system (RCCS) will be used to control the resonant frequency. The main objective of this study is to measure and transfer the resonance frequency error to the RCCS by measuring the RF eld pro le in the cavity. The algorithm derived by using a state-space model is used to represent the resonant frequency error. The control application program was developed with a VME-based PCI mezzanine card (PMC) extended board and a multitasking method based on the VxWorks. We tested the algorithm, the control board and the application program by using a dummy cavity. In this paper, the algorithm, the system con guration and the test results are presented. PACS numbers: 29.17.+w