IPAC2018 - List of Authors (Miura, A.)

Paper	Title	Page
TUPAK008	Longitudinal Bunch Size Measurements with an RF Deflector at J-PARC LINAC	974
	M. Otani, K. Futatsukawa KEK, Ibaraki, Japan K. Hirano, A. Miura JAEA/J-PARC, Tokai-mura, Japan Y. Liu KEK/JAEA, Ibaraki-Ken, Japan T. Maruta FRIB, East Lansing, USA
	Measurement of the longitudinal bunch size is important for the stable beam operation. Especially in a medium energy beam transport (MEBT) located after a radio-frequency quadrupole in J-PARC, it is necessary to measure the bunch size with minimum set of equipment to avoid subsequent emittance growth due to space charge. We had proposed a longitudinal size measurement with an rf deflector normally used for deflecting theμbunch; phase spread is migrated to spatial one if the reference particle arrives at the deflector when the voltage is rising in time and is zero. Then a buncher cavity located upstream of the deflector is utilized to scan the phase spread to measure the longitudinal beam parameters. In this poster, recent measurement results are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAK008
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WEPAL014	Non-Distructive 2-D Beam Profile Monitor Using Gas Sheet in J-PARC LINAC	2177
	J. Kamiya, Y. Hikichi, M. Kinsho, A. Miura, N. Ogiwara JAEA/J-PARC, Tokai-mura, Japan
	We have been developed a beam profile monitor using interaction between the beam and the gas molecules distributed in sheet shape. Generated luminescence or ions by passing the beam through the gas sheet has the information of cross-section shape of the beam. The gas sheet beam monitor will become a useful tool to measure the profile of high power beams because it has no breakable element such as wires and a 2-D beam profile at a certain position of beam line can be immediately obtained by just injecting the gas. Previously, the development of the gas sheet generator and successful demonstration of the beam profile measurement were reported. This time, we applied a gas sheet monitor to J-PARC LINAC, where the negative hydrogen atoms (H⁻) are accelerated to the energy of 400 MeV in the normal operation. Most challenging factor was the development of the gas sheet monitor system, which generates the enough dense gas sheet to detect the clear image of the beam profile without harmful effect on the ultra-high vacuum in the beam line. We will report the gas sheet beam monitor system for J-PARC LINAC and the results of the first measurement of the beam profile. N. Ogiwara, et al., Proceedings of IPAC2016, p.2102.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL014
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WEPAL015	Improvement of Motor Control System in J-PARC Linac and RCS	2180
	H. Takahashi, A. Miura, Y. Sawabe, M. Yoshimoto JAEA/J-PARC, Tokai-mura, Japan M. Kawase, T. Suzuki Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan
	In J-PARC, at the Linac wire scanner, the RCS collimator, and etc., a motor control system by VME is constructed as a drive system of them. Since the malfunction of operation occurred in the control system of the RCS collimator drive system in 2016, we decided to improve the motor control system. As a cause of malfunction, it is considered that aging of control equipment is one of them as J-PARC has been operated for more than 10 years. However, the defect did not occur in the reproduction test. Therefore, it can be considered that a malfunction occurred in the VME control system due to abnormality of the semiconductor element due to radiation ray. Then, in the improved motor control system, PLC with FA* specification with high reliability was adopted as the control device. Also, in case of unexpected event that a malfunction occurred in the PLC, the emergency stop mechanism was developed to stop the drive system by the signal of the limit switch, and a system incorporating it was constructed. In this paper, we show the inference of cause of the malfunction and details the improved motor control system with high safety. * Factory Automation
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL015
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WEPAL016	Tensile Fracture Test of Metallic Wire of Beam Profile Monitors	2183
	A. Miura, Y. Kawane, K. Moriya JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan S. Fukuoka Nihon Koshuha Co. Ltd, Yokohama, Japan K. Futatsukawa, T. Miyao KEK, Ibaraki, Japan
	In order to mitigate the beam loss during a beam transportation in a high-brilliant accelerator facilities, wire-based profile monitors are used to measure by both transverse and longitudinal beam profiles using wire-scanner monitors (WSMs) and bunch-shape monitors (BSMs) for the tuning of quadrupole magnets and bunching cavities. Signals are come from the direct interaction between a metallic wire and beam. We have used the tungsten wire as a high melting-point material by estimation of heat loading during the impact of beam particles. In addition, a spring is applied for the relaxing a sag under wire's own weight. A tensile fracture test is conducted by supplying an electrical current as a simulated beam-heat loading. As the results, we obtained the relation between the thermal limit to break down and tension loading of tungsten wire.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL016
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WEPAL021	Study of a Tuner for a High-Accuracy Bunch Shape Monitor	2200
	K. Moriya, Y. Kawane, A. Miura JAEA/J-PARC, Tokai-mura, Japan K. Futatsukawa, T. Miyao KEK, Ibaraki, Japan
	In the J-PARC Linac, development and higher precision of Bunch Shape Monitor (BSM) have been progressed for measuring the longitudinal beam distribution. To transform a longitudinal beam-profile into transverse one with an rf field, we need the field having an acceleration synchronizing frequency. An rf deflector of BSM consists of a half λ cylindrical cavity and two electrodes for deflection. In general, the resonance frequency can be tuned by adjusting the electrode length. We designed the new tuner with CST Studio. We can control the resonance frequency by Adjusting not only the electrode length but the cavity volume. We found the optimum lengths of electrode and volume for tuning. We introduce development of the new rf tuner for BSM in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL021
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FRXGBD3	Application of Carbon Nanotube Wire for Beam Profile Measurement of Negative Hydrogen Ion Beam	5022
	A. Miura, K. Moriya JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan T. Miyao KEK, Ibaraki, Japan
	A wire scanner monitor using metallic wire is reliably employed for the beam profile measurement in the J-PARC linac. Because the loading of negative hydrogen (H⁻) ion beam on a wire increases under high-current beam operation, we focus on using a high-durability beam profile monitors by attaching another wire material. Carbon nanotubes (CNT) are made of graphite in a cylindrical shape and have a tensile strength not less than 100 times that of steel. The electric conductivity has higher than that of metals, and hardness is endured thermally around 3000°C in a vacuum circumstance. We applied the CNT wires to WSM and measured transverse profiles with a 3-MeV and 191-MeV H⁻ beam. As a result, we obtained the equivalent signal levels taken by carbon wire made of polyacrylonitrile without any damage. In this paper, the signal response when the CNT is irradiated with an H⁻ beam and the result of beam profile measurement. In addition, the surface of CNT after 3-MeV beam operation was observed.
	Slides FRXGBD3 [2.558 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-FRXGBD3
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Paper

Title

Page

Longitudinal Bunch Size Measurements with an RF Deflector at J-PARC LINAC

974

M. Otani, K. Futatsukawa
KEK, Ibaraki, Japan
K. Hirano, A. Miura
JAEA/J-PARC, Tokai-mura, Japan
Y. Liu
KEK/JAEA, Ibaraki-Ken, Japan
T. Maruta
FRIB, East Lansing, USA

Measurement of the longitudinal bunch size is important for the stable beam operation. Especially in a medium energy beam transport (MEBT) located after a radio-frequency quadrupole in J-PARC, it is necessary to measure the bunch size with minimum set of equipment to avoid subsequent emittance growth due to space charge. We had proposed a longitudinal size measurement with an rf deflector normally used for deflecting theμbunch; phase spread is migrated to spatial one if the reference particle arrives at the deflector when the voltage is rising in time and is zero. Then a buncher cavity located upstream of the deflector is utilized to scan the phase spread to measure the longitudinal beam parameters. In this poster, recent measurement results are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-TUPAK008

Export •

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

WEPAL014

Non-Distructive 2-D Beam Profile Monitor Using Gas Sheet in J-PARC LINAC

2177

J. Kamiya, Y. Hikichi, M. Kinsho, A. Miura, N. Ogiwara
JAEA/J-PARC, Tokai-mura, Japan

We have been developed a beam profile monitor using interaction between the beam and the gas molecules distributed in sheet shape*. Generated luminescence or ions by passing the beam through the gas sheet has the information of cross-section shape of the beam. The gas sheet beam monitor will become a useful tool to measure the profile of high power beams because it has no breakable element such as wires and a 2-D beam profile at a certain position of beam line can be immediately obtained by just injecting the gas. Previously, the development of the gas sheet generator and successful demonstration of the beam profile measurement were reported. This time, we applied a gas sheet monitor to J-PARC LINAC, where the negative hydrogen atoms (H⁻) are accelerated to the energy of 400 MeV in the normal operation. Most challenging factor was the development of the gas sheet monitor system, which generates the enough dense gas sheet to detect the clear image of the beam profile without harmful effect on the ultra-high vacuum in the beam line. We will report the gas sheet beam monitor system for J-PARC LINAC and the results of the first measurement of the beam profile.
* N. Ogiwara, et al., Proceedings of IPAC2016, p.2102.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL014

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

WEPAL015

Improvement of Motor Control System in J-PARC Linac and RCS

2180

H. Takahashi, A. Miura, Y. Sawabe, M. Yoshimoto
JAEA/J-PARC, Tokai-mura, Japan
M. Kawase, T. Suzuki
Mitsubishi Electric System & Service Co., Ltd, Tsukuba, Japan

In J-PARC, at the Linac wire scanner, the RCS collimator, and etc., a motor control system by VME is constructed as a drive system of them. Since the malfunction of operation occurred in the control system of the RCS collimator drive system in 2016, we decided to improve the motor control system. As a cause of malfunction, it is considered that aging of control equipment is one of them as J-PARC has been operated for more than 10 years. However, the defect did not occur in the reproduction test. Therefore, it can be considered that a malfunction occurred in the VME control system due to abnormality of the semiconductor element due to radiation ray. Then, in the improved motor control system, PLC with FA* specification with high reliability was adopted as the control device. Also, in case of unexpected event that a malfunction occurred in the PLC, the emergency stop mechanism was developed to stop the drive system by the signal of the limit switch, and a system incorporating it was constructed. In this paper, we show the inference of cause of the malfunction and details the improved motor control system with high safety.
* Factory Automation

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL015

Export •

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

WEPAL016

Tensile Fracture Test of Metallic Wire of Beam Profile Monitors

2183

A. Miura, Y. Kawane, K. Moriya
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
S. Fukuoka
Nihon Koshuha Co. Ltd, Yokohama, Japan
K. Futatsukawa, T. Miyao
KEK, Ibaraki, Japan

In order to mitigate the beam loss during a beam transportation in a high-brilliant accelerator facilities, wire-based profile monitors are used to measure by both transverse and longitudinal beam profiles using wire-scanner monitors (WSMs) and bunch-shape monitors (BSMs) for the tuning of quadrupole magnets and bunching cavities. Signals are come from the direct interaction between a metallic wire and beam. We have used the tungsten wire as a high melting-point material by estimation of heat loading during the impact of beam particles. In addition, a spring is applied for the relaxing a sag under wire's own weight. A tensile fracture test is conducted by supplying an electrical current as a simulated beam-heat loading. As the results, we obtained the relation between the thermal limit to break down and tension loading of tungsten wire.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL016

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

WEPAL021

Study of a Tuner for a High-Accuracy Bunch Shape Monitor

2200

K. Moriya, Y. Kawane, A. Miura
JAEA/J-PARC, Tokai-mura, Japan
K. Futatsukawa, T. Miyao
KEK, Ibaraki, Japan

In the J-PARC Linac, development and higher precision of Bunch Shape Monitor (BSM) have been progressed for measuring the longitudinal beam distribution. To transform a longitudinal beam-profile into transverse one with an rf field, we need the field having an acceleration synchronizing frequency. An rf deflector of BSM consists of a half λ cylindrical cavity and two electrodes for deflection. In general, the resonance frequency can be tuned by adjusting the electrode length. We designed the new tuner with CST Studio. We can control the resonance frequency by Adjusting not only the electrode length but the cavity volume. We found the optimum lengths of electrode and volume for tuning. We introduce development of the new rf tuner for BSM in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL021

Export •

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

FRXGBD3

Application of Carbon Nanotube Wire for Beam Profile Measurement of Negative Hydrogen Ion Beam

5022

A. Miura, K. Moriya
JAEA/J-PARC, Tokai-Mura, Naka-Gun, Ibaraki-Ken, Japan
T. Miyao
KEK, Ibaraki, Japan

A wire scanner monitor using metallic wire is reliably employed for the beam profile measurement in the J-PARC linac. Because the loading of negative hydrogen (H⁻) ion beam on a wire increases under high-current beam operation, we focus on using a high-durability beam profile monitors by attaching another wire material. Carbon nanotubes (CNT) are made of graphite in a cylindrical shape and have a tensile strength not less than 100 times that of steel. The electric conductivity has higher than that of metals, and hardness is endured thermally around 3000°C in a vacuum circumstance. We applied the CNT wires to WSM and measured transverse profiles with a 3-MeV and 191-MeV H⁻ beam. As a result, we obtained the equivalent signal levels taken by carbon wire made of polyacrylonitrile without any damage. In this paper, the signal response when the CNT is irradiated with an H⁻ beam and the result of beam profile measurement. In addition, the surface of CNT after 3-MeV beam operation was observed.

Slides FRXGBD3 [2.558 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-FRXGBD3

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