IPAC2016 - List of Authors (Yanagisawa, T.)

Paper	Title	Page
WEPMB014	Cavity Performance of the Prototype KEK Superconducting RF Gun	2148
	T. Konomi, E. Kako, E. Kako, Y. Kobayashi, Y. Kobayashi, K. Umemori, K. Umemori, S. Yamaguchi KEK, Ibaraki, Japan R. Matsuda Mitsubishi Heavy Industries Ltd. (MHI), Takasago, Japan T. Yanagisawa MHI, Hiroshima, Japan
	A superconducting RF (SRF) gun can generate a high current and high energy beam. It has a possibility to achieve requirement from high performance ERL and high repetition FEL. Target values of the L-band KEK SRF gun are that beam repetition is 1.3 GHz, beam current is 100 mA, beam energy is 2 MeV, emittance is 1 mm mrad or less. The number of cell is 1.5. Accelerating energy of 2 MeV corresponds to 42 MV/m of maximum surface field. The photocathode is designed to be illuminated by excitation laser from backside. The SRF gun cavity consists of the 1.5 cell accelerating cavity, cathode plug and choke filter for protecting the heating of cathode plug. To evaluate these parts individually, these parts are added step by step. High gradient test of the accelerating cell without cathode plug and choke filter was done. The surface peak electric field reached 66 MV/m, and this meet the target value 42 MV/m sufficiently. Next high gradient test will be done after adding the choke filter. The choke filter is designed to be simple to wash choke cell easier. In this conference, we will report the design, fabrication and high gradient performance of the SRF gun cavity with choke filter.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB014
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WEPMB016	Vertical Test Results of Nitrogen Doped SRF Cavities at KEK	2154
	K. Umemori, H. Inoue, E. Kako, T. Konomi, T. Kubo, H. Sakai, H. Shimizu, M. Yamanaka KEK, Ibaraki, Japan H. Hara, K. Sennyu, T. Yanagisawa MHI-MS, Kobe, Japan
	Recently Nitrogen doping(N-doping) technique was proposed and drastic improvements of Q-values were reported. Since high-Q operation of SRF cavities are very attractive for CW machine, we started investigation on performance of Nitrogen doped SRF cavities. Nitrogen doping systems were prepared on two vacuum furnaces, which have been used for annealing of SRF cavities. Two fine grain single cell cavities have been used for the study. After 800 degree, 3 hours annealing, N-doping were carried out under several Pa of Nitrogen pressure and followed by post annealing. Three kind of different conditions, pressure and duration time, were attempted. After applying EP-2, cavity performances were evaluated by vertical tests. Against our expectations, we observed lower Q-values, at every measurements, than those measured without N-doping. In this presentation, we describe details about N-doping system and parameters and results obtained by vertical tests. Some discussions are also given against our results.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB016
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WEPMB026	MHI-MS's Production Activities of Superconducting Cavity	2180
	H. Hara, A. Miyamoto, K. Sennyu, T. Yanagisawa MHI-MS, Kobe, Japan E. Kako, T. Konomi, H. Nakai, K. Umemori KEK, Ibaraki, Japan
	Mitsubishi Heavy Industries Mechatronics Systems, Ltd. (MHI-MS), a subsidiary of MHI, took over MHI's accelerator business on October 1, 2015, and has been developing the business since that time. MHI-MS has developed manufacturing process of superconducting cavities continuously. In this presentation, recent progress will be reported.
DOI •	reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB026
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Paper

Title

Page

Cavity Performance of the Prototype KEK Superconducting RF Gun

2148

T. Konomi, E. Kako, E. Kako, Y. Kobayashi, Y. Kobayashi, K. Umemori, K. Umemori, S. Yamaguchi
KEK, Ibaraki, Japan
R. Matsuda
Mitsubishi Heavy Industries Ltd. (MHI), Takasago, Japan
T. Yanagisawa
MHI, Hiroshima, Japan

A superconducting RF (SRF) gun can generate a high current and high energy beam. It has a possibility to achieve requirement from high performance ERL and high repetition FEL. Target values of the L-band KEK SRF gun are that beam repetition is 1.3 GHz, beam current is 100 mA, beam energy is 2 MeV, emittance is 1 mm mrad or less. The number of cell is 1.5. Accelerating energy of 2 MeV corresponds to 42 MV/m of maximum surface field. The photocathode is designed to be illuminated by excitation laser from backside. The SRF gun cavity consists of the 1.5 cell accelerating cavity, cathode plug and choke filter for protecting the heating of cathode plug. To evaluate these parts individually, these parts are added step by step. High gradient test of the accelerating cell without cathode plug and choke filter was done. The surface peak electric field reached 66 MV/m, and this meet the target value 42 MV/m sufficiently. Next high gradient test will be done after adding the choke filter. The choke filter is designed to be simple to wash choke cell easier. In this conference, we will report the design, fabrication and high gradient performance of the SRF gun cavity with choke filter.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB014

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WEPMB016

Vertical Test Results of Nitrogen Doped SRF Cavities at KEK

2154

K. Umemori, H. Inoue, E. Kako, T. Konomi, T. Kubo, H. Sakai, H. Shimizu, M. Yamanaka
KEK, Ibaraki, Japan
H. Hara, K. Sennyu, T. Yanagisawa
MHI-MS, Kobe, Japan

Recently Nitrogen doping(N-doping) technique was proposed and drastic improvements of Q-values were reported. Since high-Q operation of SRF cavities are very attractive for CW machine, we started investigation on performance of Nitrogen doped SRF cavities. Nitrogen doping systems were prepared on two vacuum furnaces, which have been used for annealing of SRF cavities. Two fine grain single cell cavities have been used for the study. After 800 degree, 3 hours annealing, N-doping were carried out under several Pa of Nitrogen pressure and followed by post annealing. Three kind of different conditions, pressure and duration time, were attempted. After applying EP-2, cavity performances were evaluated by vertical tests. Against our expectations, we observed lower Q-values, at every measurements, than those measured without N-doping. In this presentation, we describe details about N-doping system and parameters and results obtained by vertical tests. Some discussions are also given against our results.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB016

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPMB026

MHI-MS's Production Activities of Superconducting Cavity

2180

H. Hara, A. Miyamoto, K. Sennyu, T. Yanagisawa
MHI-MS, Kobe, Japan
E. Kako, T. Konomi, H. Nakai, K. Umemori
KEK, Ibaraki, Japan

Mitsubishi Heavy Industries Mechatronics Systems, Ltd. (MHI-MS), a subsidiary of MHI, took over MHI's accelerator business on October 1, 2015, and has been developing the business since that time. MHI-MS has developed manufacturing process of superconducting cavities continuously. In this presentation, recent progress will be reported.

DOI •

reference for this paper ※ DOI:10.18429/JACoW-IPAC2016-WEPMB026

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reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)