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The 100 MeV Linac of the Proton Engineering Frontier Project (PEFP) consists of an ion source, a low energy beam transport (LEBT), a 3 MeV radio frequency quadrupole (RFQ), and an 100 MeV drift tube linac (DTL). The DTL is separated into two parts. The first part includes 4 tanks which accelerate 20 mA proton beams up to 20 MeV. The medium energy beam transport (MEBT) follows the 20 MeV accelerator in order to match the proton beams into the next linac as well as to extract and supply 20 MeV proton beams to the user facilities. The second part of the DTL consists of 7 tanks to accelerate proton beams to 100 MeV. This work focuses on an error analysis of the designed 100 MeV linac in order to study the steering magnets which control the beam fluctuations and reduce the potential beam loss.

The RF amplitude and the phase stability requirements of the LLRF system for the PEFP (Proton Engineering Frontier Project) proton linac are within 1% and 1 degree, respectively. As a prototype of the LLRF, a simple digital PI control system based on commercial FPGA board is designed and tested. The main features are a sampling rate of 40 MHz which is four times higher than the down- converted cavity signal frequency, digital in-phase and quadrature detection, pulsed mode operation with the external trigger, and a simple proportional-integral feedback algorithm implemented in a FPGA. The developed system was tested with 3 MeV RFQ and 20 MeV DTL, and satisfied the stability requirements.

The beam test of the Proton Engineering Frontier Project (PEFP) 20 MeV proton linear accelerator started again, after the upgrade of the RF control system. One of the important goals during this test period is to increase the beam current to the design level. Various current transformers were installed along the linac to measure the beam current itself and possible beam loss along the accelerator. Also two sets of beam position and phase monitors (BPPM) were installed at the end of the 20 MeV accelerator to measure not only the beam position and phase but also the beam energy. In this paper, the overall test results including beam current and energy measurement are presented.

The temperature-controlled water cooling system has been designed to obtain the resonance frequency stabilization of the normal conducting drift tube linac (DTL) for the PEFP 100 MeV proton linear accelerator. The sizing of individual closed-loop low conductivity cooling water pumping skids for each DTL system is conducted with a simulation of thermo-hydraulic network model. The temperature control schemes incorporating the process dynamic model of heat exchangers is examined to regulate the input water temperatures into the DTL during transient and steady state operation.

A conventional 20 MeV drift tube linac (DTL) for the Proton Engineering Frontier Project (PEFP) has been developed as a low energy section of 100 MeV accelerator. The machine consists of four tanks with 152 cells supplied with 900 kW RF power from 350 MHz klystron through the ridge-loaded waveguide coupler. We assembled the fabricated accelerator components and aligned each part with care. We have also prepared the subsystems for the test of the DTL such as RF power delivery system, high voltage DC power supply, vacuum system, cooling system, measurements and control system and so on. The detailed description of the initial test setup and preliminary test results will be given in this paper.

A 100 MeV proton accelerator is under development for the Proton Engineering Frontier Project (PEFP). The goal of the first stage of the project is to develop a 20MeV accelerator and the initial test of the 20 MeV accelerator will be made. The DTL of 20 MeV accelerator consists of four tanks and will be driven with single klystron, which gives rise to some unique problems with regard to the way of independent resonance control for each tank. Some changes made in the LLRF for reducing phase or amplitude error of cavities affect all of four tanks simultaneously, for which it is not possible to use LLRF for individual control of phase and amplitude of each tank. For independent control of each tank, we are going to use the temperature control of the drift tubes as a frequency tuner. During the initial test of the DTL, the phase of each tank will be synchronized with the first tank phase, and beam based test will be performed as if all of tanks were single unit. The detailed description of the test scheme and the analysis results will be given in this paper.

A 100MeV proton accelerator has been developed at PEFP (Proton Engineering Frontier Project) as a 21C Frontier Project [1]. The goal of the first phase of the project is to develop a 20MeV accelerator. The 20MeV accelerator consists of in source, LEBT, 3MeV RFQ and 20MeV DTL. The 3MeV RFQ was already installed and being tested [2]. During preliminary test, some problems have been found out. Therefore it was decided to fabricate another RFQ. The RFQ upgrade includes some characteristics such as constant voltage profile, adoption of transition cell which are different from present one. In this paper, the fabrication of the PEFP 3MeV RFQ upgrade is presented.

The 100 MeV Proton linear accelerator (Linac) for the PEFP (Proton Engineering Frontier Project) will include one RFQ and one DTL1 at 350 MHz as well as seven DTL2 cavities at 700 MHz. The low level RF system with the digital feedback RF control provides the field control to accelerate a 20mA proton beam from 50 keV to 20 MeV with a RFQ and a DTL1 at 350 MHz. The FPGA-based digital feedback RF control system has been built and is used to control cavity field amplitude within ± 1% and relative phase within ± 1°. The fast digital processing is networked to the EPICS-based control system with an embedded processor (Blackfin).

A MEBT system of the Proton Engineering Frontier Project (PEFP) has to be installed after the 20 MeV DTL where a beam extraction system will be positioned to supply 20 MeV proton beams to the user group. This implies a large drift space which can be a serious potential problem in the longitudinal beam matching between the DTL and the following accelerating structure. The MEBT consists of 8 quadrupole magnets and 2 buncher cavities. The initial 4 quadrupoles is controlling the beam size in the bending magnet for beam extraction. The transverse beam matching is achieved by the following 4 magnets. The buncher cavities are for the longitudinal beam matching.

Summary form only given, as follows. Beam dynamics study of a conventional DTL to accelerate proton beam of 20 mA from 3 MeV to 20 MeV has been done for the Proton Engineering Frontier Project (PEFP) in Korea. It consists of the 4 DTL tanks-supplied with 350 MHz RF from one 1 MW klystron. We adopt a 4 /spl beta//spl lambda/ FFDD lattice structure of electromagnet quadrupoles.

The 10 MeV, 100 kW CW electron accelerator (FANTRON I) is being developed in Department of Nuclear Engineering, Seoul National University (SNU). The X-ray generated by the accelerated electron beam will be used in sterilizing the agricultural, forest and aquatic products. For the effective irradiation and the safety of the irradiated products, uniform irradiation is needed. The designed target is mainly featured by the radially focused uniform X-ray. The diameter of irradiation hole is 0.75 m. And the generated X-ray is emitted toward the center of the irradiation hole with uniform distribution along the circumference. To generate the radially focused uniform X-ray, the accelerated electron beam must be focused radially on the target that is the outer shell of the irradiation hole with high uniformity.

The application fields of intense gamma-rays or X-rays for industrial purposes are expanding. An electron beam accelerator which can generate X-rays whose dose rate is equivalent to the effect of a several MCi gamma-ray source is a major candidate as an intense X-ray source. The 10 MeV, 100 kW CW electron accelerator Fantron-I is conceptually designed for an X-ray source to irradiate food, corn, forest products and so on. Electrons are accelerated seventeen times through two coaxial cavities with a TM010 mode by means of a bending magnet located outside the cavity. The resonant frequency of the cavity is about 160 MHz and the phase of one cavity is 180/spl deg/ shifted from that of the other. Higher order modes (HOM) which may cause beam instability are analyzed. The design parameters of beam lines and bending magnets are determined from the results of beam phase analysis, especially magnetic flux density and locations of each bending magnet are carefully adjusted to synchronize the beam with the accelerating field. In this paper, characteristics and the overall conceptual design of the Fantron-I are presented.