LINAC2016 - List of Authors (Iwashita, Y.)

Paper	Title	Page
MOOP07	Development of Ultracold Neutron Accelerator for Time Focusing of Pulsed Neutrons	56
MOPRC001	use link to see paper's listing under its alternate paper code
SPWR015	use link to see paper's listing under its alternate paper code
	S. Imajo Kyoto University, Kyoto, Japan T. Ino, K. Mishima KEK, Ibaraki, Japan Y. Iwashita Kyoto ICR, Uji, Kyoto, Japan M. Kitaguchi, H.M. Shimizu Nagoya University, Nagoya, Japan S. Yamashita ICEPP, Tokyo, Japan
	Low energy neutron accelerator can be realized by the combination of an adiabatic fast passage spin flipper and a gradient magnetic field. Neutrons have magnetic moments, so that the accumulated potential energies are not cancelled before and after passage of a magnetic field and their kinetic energies change in case their spins are flipped in the field. This accelerator handles lower kinetic energy neutrons than approximately 300 neV. Currently we have developed the advanced version which makes it possible to handle broader kinetic energy range. The design and measured characteristics are described.
	Slides MOOP07 [1.313 MB]
	Poster MOOP07 [1.389 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOOP07
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MOPLR035	Fabrication of Superconducting Spoke Cavity for Compact Photon Source	212
	M. Sawamura, R. Hajima QST, Tokai, Japan H. Hokonohara, Y. Iwashita, H. Tongu Kyoto ICR, Uji, Kyoto, Japan T. Kubo, T. Saeki KEK, Ibaraki, Japan
	Funding: This study is supported by Photon and Quantum Basic Research Coordinated Development Program of MEXT, Japan. The spoke cavity is expected to have advantages for compact ERL accelerator for X-ray source based on laser Compton scattering. We have been developing the spoke cavity under a research program of MEXT, Japan to establish the fabrication process. Since our designed shape of the spoke is complicated due to increase the RF properties, one-step press forming with one set of molds will cause so large strain to break the sheet. We designed the mold components including the process of press work. The press forming tests of the spoke cavity have been done with the various materials of sheets to check molding performance. In this paper we present status of the spoke cavity fabrication.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOPLR035
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MOPLR036	Study on Multilayer Thin Film Coating on Superconducting Cavity	215
	Y. Iwashita, Y. Fuwa, H. Tongu Kyoto ICR, Uji, Kyoto, Japan H. Hayano, T. Kubo, T. Saeki KEK, Ibaraki, Japan M. Hino Kyoto University, Research Reactor Institute, Osaka, Japan H. Oikawa Utsunomiya University, Utsunomiya, Japan
	Funding: This research is supported by following programs: Grant-in-Aid for Exploratory Research 26600142 and Photon and Quantum Basic Research Coordinated Development Program from the MEXT. Multilayer thin film coating is a promising technology to enhance performance of superconducting cavities. Until recently, principal parameters to achieve the sufficient performance had not been known, such as the thickness of each layer. We proposed a method to deduce a set of the parameters to exhibit a good performances. In order to verify the scheme, we are trying to make some experiments on the subject at Kyoto. The sample preparation and the test setup for the measurement apparatus will be discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOPLR036
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TUPLR054	RFQ Vane Shapes for Efficient Acceleration	581
	Y. Iwashita, Y. Fuwa Kyoto ICR, Uji, Kyoto, Japan R.A. Jameson IAP, Frankfurt am Main, Germany
	RFQ vane shapes for efficient acceleration are under investigation by introducing more terms in addition to the two term potential. They can incorporate with the feature of the trapezoidal shape modulation with less multipole components, while higher acceleration efficiency is expected. The simulation study will be presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR054
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THPLR006	Design Study of a Test Cavity for Evaluating RF Critical Magnetic Field of Thin-Film Superconductor	852
	H. Oikawa Utsunomiya University, Utsunomiya, Japan H. Hayano, S. Kato, T. Kubo, T. Saeki KEK, Ibaraki, Japan T. Higashiguchi Center for Optical Research and Education, Utsunomiya University, Utsunomiya, Japan M. Hino Kyoto University, Research Reactor Institute, Osaka, Japan Y. Iwashita Kyoto ICR, Uji, Kyoto, Japan
	Superconducting cavities of higher gradient has been demanded in various fields of the accelerator science. Also, according to the Technical Design Report (TDR) of International Linear Collider (ILC), the higher gradient of 45 MV/m is required in the second stage of ILC. To realize such higher gradient, several methods are proposed. One of such methods is to coat multi-layer thin-film superconductor on the inner surface of RF cavity where the thin film increases the RF critical field on the inner surface of the cavity. To demonstrate the RF performance of thin-film structure on a small coupon sample, we designed the RF mushroom-shaped cavity with which the RF critical magnetic field is measured on a thin-film coupon sample set on the inner surface of the cavity. If the RF cavity is cooled down below the critical temperature of thin-film superconductor with supplying RF power, the heat dissipation might be measured on the coupon sample in the cavity. We designed the shape of the cavity so as to produce a strong RF magnetic field parallel to the sample surface efficiently. We report the design, manufacturing and RF property measurements of the cavity in this presentation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR006
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FR1A05	Development of a Muon Linac for the G-2/EDM Experiment at J-PARC	1037
	M. Otani, N. Kawamura, T. Mibe, F. Naito, M. Yoshida KEK, Ibaraki, Japan K. Hasegawa, Y. Kondo JAEA, Ibaraki-ken, Japan N. Hayashizaki RLNR, Tokyo, Japan T. Ito JAEA/J-PARC, Tokai-mura, Japan Y. Iwashita Kyoto ICR, Uji, Kyoto, Japan Y. Iwata NIRS, Chiba-shi, Japan R. Kitamura University of Tokyo, Tokyo, Japan N. Saito J-PARC, KEK & JAEA, Ibaraki-ken, Japan
	Precision measurements of the muon's anomalous magnetic moment (g-2) and electric dipole moment (EDM) are one of the effective ways to test the standard model. An ultra-cold muon beam is generated from a surface muon beam by a thermal muonium production and accelerated to 300 MeV/c by a linac. The muon linac consists of an RFQ, an inter-digital IH, a Disk And Washer structure, and a disk loaded structure. The ultra-cold muons will have an extremely small momentum spread of 0.3 % with a normalized transverse emittance of around 1.5 pi mm-mrad. The design and status of the muon linac at J-PARC will be presented.
	Slides FR1A05 [13.154 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-FR1A05
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

MOOP07

Development of Ultracold Neutron Accelerator for Time Focusing of Pulsed Neutrons

56

MOPRC001

use link to see paper's listing under its alternate paper code

SPWR015

use link to see paper's listing under its alternate paper code

S. Imajo
Kyoto University, Kyoto, Japan
T. Ino, K. Mishima
KEK, Ibaraki, Japan
Y. Iwashita
Kyoto ICR, Uji, Kyoto, Japan
M. Kitaguchi, H.M. Shimizu
Nagoya University, Nagoya, Japan
S. Yamashita
ICEPP, Tokyo, Japan

Low energy neutron accelerator can be realized by the combination of an adiabatic fast passage spin flipper and a gradient magnetic field. Neutrons have magnetic moments, so that the accumulated potential energies are not cancelled before and after passage of a magnetic field and their kinetic energies change in case their spins are flipped in the field. This accelerator handles lower kinetic energy neutrons than approximately 300 neV. Currently we have developed the advanced version which makes it possible to handle broader kinetic energy range. The design and measured characteristics are described.

Slides MOOP07 [1.313 MB]

Poster MOOP07 [1.389 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOOP07

Export •

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

MOPLR035

Fabrication of Superconducting Spoke Cavity for Compact Photon Source

212

M. Sawamura, R. Hajima
QST, Tokai, Japan
H. Hokonohara, Y. Iwashita, H. Tongu
Kyoto ICR, Uji, Kyoto, Japan
T. Kubo, T. Saeki
KEK, Ibaraki, Japan

Funding: This study is supported by Photon and Quantum Basic Research Coordinated Development Program of MEXT, Japan.
The spoke cavity is expected to have advantages for compact ERL accelerator for X-ray source based on laser Compton scattering. We have been developing the spoke cavity under a research program of MEXT, Japan to establish the fabrication process. Since our designed shape of the spoke is complicated due to increase the RF properties, one-step press forming with one set of molds will cause so large strain to break the sheet. We designed the mold components including the process of press work. The press forming tests of the spoke cavity have been done with the various materials of sheets to check molding performance. In this paper we present status of the spoke cavity fabrication.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOPLR035

Export •

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

MOPLR036

Study on Multilayer Thin Film Coating on Superconducting Cavity

215

Y. Iwashita, Y. Fuwa, H. Tongu
Kyoto ICR, Uji, Kyoto, Japan
H. Hayano, T. Kubo, T. Saeki
KEK, Ibaraki, Japan
M. Hino
Kyoto University, Research Reactor Institute, Osaka, Japan
H. Oikawa
Utsunomiya University, Utsunomiya, Japan

Funding: This research is supported by following programs: Grant-in-Aid for Exploratory Research 26600142 and Photon and Quantum Basic Research Coordinated Development Program from the MEXT.
Multilayer thin film coating is a promising technology to enhance performance of superconducting cavities. Until recently, principal parameters to achieve the sufficient performance had not been known, such as the thickness of each layer. We proposed a method to deduce a set of the parameters to exhibit a good performances. In order to verify the scheme, we are trying to make some experiments on the subject at Kyoto. The sample preparation and the test setup for the measurement apparatus will be discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-MOPLR036

Export •

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

TUPLR054

RFQ Vane Shapes for Efficient Acceleration

581

Y. Iwashita, Y. Fuwa
Kyoto ICR, Uji, Kyoto, Japan
R.A. Jameson
IAP, Frankfurt am Main, Germany

RFQ vane shapes for efficient acceleration are under investigation by introducing more terms in addition to the two term potential. They can incorporate with the feature of the trapezoidal shape modulation with less multipole components, while higher acceleration efficiency is expected. The simulation study will be presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-TUPLR054

Export •

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

THPLR006

Design Study of a Test Cavity for Evaluating RF Critical Magnetic Field of Thin-Film Superconductor

852

H. Oikawa
Utsunomiya University, Utsunomiya, Japan
H. Hayano, S. Kato, T. Kubo, T. Saeki
KEK, Ibaraki, Japan
T. Higashiguchi
Center for Optical Research and Education, Utsunomiya University, Utsunomiya, Japan
M. Hino
Kyoto University, Research Reactor Institute, Osaka, Japan
Y. Iwashita
Kyoto ICR, Uji, Kyoto, Japan

Superconducting cavities of higher gradient has been demanded in various fields of the accelerator science. Also, according to the Technical Design Report (TDR) of International Linear Collider (ILC), the higher gradient of 45 MV/m is required in the second stage of ILC. To realize such higher gradient, several methods are proposed. One of such methods is to coat multi-layer thin-film superconductor on the inner surface of RF cavity where the thin film increases the RF critical field on the inner surface of the cavity. To demonstrate the RF performance of thin-film structure on a small coupon sample, we designed the RF mushroom-shaped cavity with which the RF critical magnetic field is measured on a thin-film coupon sample set on the inner surface of the cavity. If the RF cavity is cooled down below the critical temperature of thin-film superconductor with supplying RF power, the heat dissipation might be measured on the coupon sample in the cavity. We designed the shape of the cavity so as to produce a strong RF magnetic field parallel to the sample surface efficiently. We report the design, manufacturing and RF property measurements of the cavity in this presentation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-THPLR006

Export •

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

FR1A05

Development of a Muon Linac for the G-2/EDM Experiment at J-PARC

1037

M. Otani, N. Kawamura, T. Mibe, F. Naito, M. Yoshida
KEK, Ibaraki, Japan
K. Hasegawa, Y. Kondo
JAEA, Ibaraki-ken, Japan
N. Hayashizaki
RLNR, Tokyo, Japan
T. Ito
JAEA/J-PARC, Tokai-mura, Japan
Y. Iwashita
Kyoto ICR, Uji, Kyoto, Japan
Y. Iwata
NIRS, Chiba-shi, Japan
R. Kitamura
University of Tokyo, Tokyo, Japan
N. Saito
J-PARC, KEK & JAEA, Ibaraki-ken, Japan

Precision measurements of the muon's anomalous magnetic moment (g-2) and electric dipole moment (EDM) are one of the effective ways to test the standard model. An ultra-cold muon beam is generated from a surface muon beam by a thermal muonium production and accelerated to 300 MeV/c by a linac. The muon linac consists of an RFQ, an inter-digital IH, a Disk And Washer structure, and a disk loaded structure. The ultra-cold muons will have an extremely small momentum spread of 0.3 % with a normalized transverse emittance of around 1.5 pi mm-mrad. The design and status of the muon linac at J-PARC will be presented.

Slides FR1A05 [13.154 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2016-FR1A05

Export •

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