SRF2015 - List of Authors (Nakai, H.)

Paper	Title	Page
TUPB109	Assembly and Cool-Down Tests of STF2 Cryomodule at KEK	888
	T. Shishido, K. Hara, E. Kako, Y. Kojima, H. Nakai, Y. Yamamoto KEK, Ibaraki, Japan
	As the next step of the quantum beam project, the STF2 project is in progress at KEK. Eight 9-cell SC cavities and one superconducting quardrapole magnet were assembled into the cryomodule called CM1. Four 9-cell SC cavities were assembled into the cryomodule called CM2a. These two cryomodules were connected as one unit, and the examination of completion by a prefectural government was carried out. The target value of beam energy in the STF2 accelerator is 400 MeV with a beam current of 6 mA. The first cool down test for low power level RF measurements was performed in autumn of 2014. In this paper, the assembly procedure of the STF2 cryomodules and the results of the low-power measurement are reported.
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WEBA06	Design Studies for Quarter-Wave Resonators and Cryomodules for the Riken SC-LINAC	976
	N. Sakamoto, O. Kamigaito, H. Okuno, K. Ozeki, K. Suda, Y. Watanabe, K. Yamada RIKEN Nishina Center, Wako, Japan H. Hara, K. Okihira, K. Sennyu, T. Yanagisawa MHI, Hiroshima, Japan E. Kako, H. Nakai, K. Umemori KEK, Ibaraki, Japan
	Recently we proposed a new project aimed at intensity upgrade of uranium beams of RIKEN RIBF. In this new project, construction of a superconducting linac is planned replacing the injector cyclotron so called RRC. The RIKEN superconducting linac consists of 14 cryomodules each of which contains four quarter-wave-resonators (QWRs) in each. The QWR operates at an rf frequency of 73 MHz in the continuous wave mode with beta as low as 0.055-1.008. A coaxial probe-type RF fundamental power-coupler which transmits RF power of several kW will be utilized for beam loading of 1.3 kW/resonator at the maximum with Qext of several x10⁶. Tuning of the resonant frequency will be realized with a mechanical tuner pressing the resonator wall in the direction parallel to the beam. This year, we started a development of a test cryomodule with SC-QWRs. In this paper, design studies for a SC-QWR and its cryomodule, e.g., QWR, coupler, and, tuner will be presented together with a construction schedule of the prototype. Prototyping of a superconducting cavity and its test cryomodule was funded by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan).
	Slides WEBA06 [17.564 MB]
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THPB084	Design of Input Coupler for RIKEN Superconducting Quarter-Wavelength Resonator	1335
	K. Ozeki, O. Kamigaito, H. Okuno, N. Sakamoto, K. Suda, Y. Watanabe, K. Yamada RIKEN Nishina Center, Wako, Japan E. Kako, H. Nakai, K. Umemori KEK, Ibaraki, Japan K. Okihira, K. Sennyu, T. Yanagisawa MHI, Hiroshima, Japan
	In RIKEN Nishina Center, for the purpose of development of elemental technology for the superconducting linear accelerator, the designing and construction of accelerator system based on superconducting quarter-wavelength resonator are carried out. The basic designs of the input coupler are as follows: The resonance frequency of the cavity is 75.5 MHz and assumed beam loading is about 1 kW. Double vacuum windows, which are disk-type, are adopted. A thermal anchor of 40 K is installed near the cold-window. The optimum positions of the cold-window and the thermal anchor depending on the effective RRR of copper-plate are being studied. In this contribution, the details of these designs will be reported. This work was funded by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan).
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Paper

Title

Page

Assembly and Cool-Down Tests of STF2 Cryomodule at KEK

888

T. Shishido, K. Hara, E. Kako, Y. Kojima, H. Nakai, Y. Yamamoto
KEK, Ibaraki, Japan

As the next step of the quantum beam project, the STF2 project is in progress at KEK. Eight 9-cell SC cavities and one superconducting quardrapole magnet were assembled into the cryomodule called CM1. Four 9-cell SC cavities were assembled into the cryomodule called CM2a. These two cryomodules were connected as one unit, and the examination of completion by a prefectural government was carried out. The target value of beam energy in the STF2 accelerator is 400 MeV with a beam current of 6 mA. The first cool down test for low power level RF measurements was performed in autumn of 2014. In this paper, the assembly procedure of the STF2 cryomodules and the results of the low-power measurement are reported.

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reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)

WEBA06

Design Studies for Quarter-Wave Resonators and Cryomodules for the Riken SC-LINAC

976

N. Sakamoto, O. Kamigaito, H. Okuno, K. Ozeki, K. Suda, Y. Watanabe, K. Yamada
RIKEN Nishina Center, Wako, Japan
H. Hara, K. Okihira, K. Sennyu, T. Yanagisawa
MHI, Hiroshima, Japan
E. Kako, H. Nakai, K. Umemori
KEK, Ibaraki, Japan

Recently we proposed a new project aimed at intensity upgrade of uranium beams of RIKEN RIBF. In this new project, construction of a superconducting linac is planned replacing the injector cyclotron so called RRC. The RIKEN superconducting linac consists of 14 cryomodules each of which contains four quarter-wave-resonators (QWRs) in each. The QWR operates at an rf frequency of 73 MHz in the continuous wave mode with beta as low as 0.055-1.008. A coaxial probe-type RF fundamental power-coupler which transmits RF power of several kW will be utilized for beam loading of 1.3 kW/resonator at the maximum with Qext of several x10⁶. Tuning of the resonant frequency will be realized with a mechanical tuner pressing the resonator wall in the direction parallel to the beam. This year, we started a development of a test cryomodule with SC-QWRs. In this paper, design studies for a SC-QWR and its cryomodule, e.g., QWR, coupler, and, tuner will be presented together with a construction schedule of the prototype. Prototyping of a superconducting cavity and its test cryomodule was funded by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan).

Slides WEBA06 [17.564 MB]

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THPB084

Design of Input Coupler for RIKEN Superconducting Quarter-Wavelength Resonator

1335

K. Ozeki, O. Kamigaito, H. Okuno, N. Sakamoto, K. Suda, Y. Watanabe, K. Yamada
RIKEN Nishina Center, Wako, Japan
E. Kako, H. Nakai, K. Umemori
KEK, Ibaraki, Japan
K. Okihira, K. Sennyu, T. Yanagisawa
MHI, Hiroshima, Japan

In RIKEN Nishina Center, for the purpose of development of elemental technology for the superconducting linear accelerator, the designing and construction of accelerator system based on superconducting quarter-wavelength resonator are carried out. The basic designs of the input coupler are as follows: The resonance frequency of the cavity is 75.5 MHz and assumed beam loading is about 1 kW. Double vacuum windows, which are disk-type, are adopted. A thermal anchor of 40 K is installed near the cold-window. The optimum positions of the cold-window and the thermal anchor depending on the effective RRR of copper-plate are being studied. In this contribution, the details of these designs will be reported. This work was funded by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan).

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reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)