LINAC2014 - List of Authors (Matsumoto, H.)

Paper	Title	Page
MOPP074	Digital Filters Used for Digital Feedback System at cERL	227
	F. Qiu, D.A. Arakawa, H. Katagiri, H. Matsumoto, S. Michizono, T. Miura KEK, Ibaraki, Japan
	As a test facility for the future KEK 3-GeV energy recovery linac (ERL) project, the compact ERL (cERL) features three two-cell cavities for the injector and two nine-cell cavities for the main linac. Digital low-level radio frequency (LLRF) systems have been developed to realize highly accurate RF control. In order to reduce the influence of clock jitter and to suppress the parasitic modes in the multi-cell cavities, we have developed several types of digital filters, including a first-order IIR filter, a fourth-order conjugate poles IIR filter and a notch filter. Furthermore, to design a more effective and robust controller (such as an H-infinite controller, or repetitive controller), we need to acquire more detailed system knowledge. This knowledge can be gained by using modern system identification methods. In this paper, we present the latest applications in the LLRF systems of the cERL. identification methods. In this paper, we have compared the performance of these different type filters in cERL. The preliminary result of the system identification will be also described.

MOPP076	Construction of an Accelerator-based BNCT Facility at yhe Ibaraki Neutron Medical Research Center	230
	M. Yoshioka, H. Kobayashi, T. Kurihara, S.-I. Kurokawa, H. Matsumoto, N. Matsumoto KEK, Ibaraki, Japan T. Hashirano, T. Sugano MHI, Hiroshima, Japan F. Hiraga Hokkaido University, Sapporo, Japan H. Kumada, Su. Tanaka Tsukuba University, Graduate School of Comprehensive Human Sciences, Ibaraki, Japan A. Matsumura, H. Sakurai Tsukuba University, Ibaraki, Japan N. Nagura, T. Ohba Nippon Advanced Technology Co. Ltd., Ibaraki-prefecture, Japan T.N. Nakamoto, T. Zagar Cosylab, Ljubljana, Slovenia T. Nakamura JAEA, Ibaraki-ken, Japan T. Ouchi ATOX, Ibaraki, Japan
	An accelerator-based BNCT (Boron Neutron Capture Therapy) facility is being constructed at the Ibaraki Neutron Medical Research Center. It consists of a proton linac of 80kW beam power with 8 MeV energy and 10mA average current, a beryllium target, and a moderator system to provide an epi-thermal neutron flux enough for patient treatment. The technology choices for this present system were driven by the need to site the facility in a hospital and where low residual activity is essential. The maximum neutron energy produced from an 8 MeV-proton is 6 MeV, which is below the threshold energy of the main nuclear reactions which produce radioactive products. The down side of this technology choice is that it produces a high density heat load on the target so that cooling and hydrogen aniti-blistering amelioration prevent sever challenges requiring successful R&D progress. The latest design of the target and moderator system shows that a flux of 4×10⁹ epi-thermal neutrons / cm² / sec can be obtained. This is much higher than the flux from the existing nuclear reactor based BNCT facility at JAEA ( JRR-4).

Paper

Title

Page

Digital Filters Used for Digital Feedback System at cERL

227

F. Qiu, D.A. Arakawa, H. Katagiri, H. Matsumoto, S. Michizono, T. Miura
KEK, Ibaraki, Japan

As a test facility for the future KEK 3-GeV energy recovery linac (ERL) project, the compact ERL (cERL) features three two-cell cavities for the injector and two nine-cell cavities for the main linac. Digital low-level radio frequency (LLRF) systems have been developed to realize highly accurate RF control. In order to reduce the influence of clock jitter and to suppress the parasitic modes in the multi-cell cavities, we have developed several types of digital filters, including a first-order IIR filter, a fourth-order conjugate poles IIR filter and a notch filter. Furthermore, to design a more effective and robust controller (such as an H-infinite controller, or repetitive controller), we need to acquire more detailed system knowledge. This knowledge can be gained by using modern system identification methods. In this paper, we present the latest applications in the LLRF systems of the cERL. identification methods. In this paper, we have compared the performance of these different type filters in cERL. The preliminary result of the system identification will be also described.

MOPP076

Construction of an Accelerator-based BNCT Facility at yhe Ibaraki Neutron Medical Research Center

230

M. Yoshioka, H. Kobayashi, T. Kurihara, S.-I. Kurokawa, H. Matsumoto, N. Matsumoto
KEK, Ibaraki, Japan
T. Hashirano, T. Sugano
MHI, Hiroshima, Japan
F. Hiraga
Hokkaido University, Sapporo, Japan
H. Kumada, Su. Tanaka
Tsukuba University, Graduate School of Comprehensive Human Sciences, Ibaraki, Japan
A. Matsumura, H. Sakurai
Tsukuba University, Ibaraki, Japan
N. Nagura, T. Ohba
Nippon Advanced Technology Co. Ltd., Ibaraki-prefecture, Japan
T.N. Nakamoto, T. Zagar
Cosylab, Ljubljana, Slovenia
T. Nakamura
JAEA, Ibaraki-ken, Japan
T. Ouchi
ATOX, Ibaraki, Japan

An accelerator-based BNCT (Boron Neutron Capture Therapy) facility is being constructed at the Ibaraki Neutron Medical Research Center. It consists of a proton linac of 80kW beam power with 8 MeV energy and 10mA average current, a beryllium target, and a moderator system to provide an epi-thermal neutron flux enough for patient treatment. The technology choices for this present system were driven by the need to site the facility in a hospital and where low residual activity is essential. The maximum neutron energy produced from an 8 MeV-proton is 6 MeV, which is below the threshold energy of the main nuclear reactions which produce radioactive products. The down side of this technology choice is that it produces a high density heat load on the target so that cooling and hydrogen aniti-blistering amelioration prevent sever challenges requiring successful R&D progress. The latest design of the target and moderator system shows that a flux of 4×10⁹ epi-thermal neutrons / cm² / sec can be obtained. This is much higher than the flux from the existing nuclear reactor based BNCT facility at JAEA ( JRR-4).