IPAC2018 - List of Authors (Qiu, F.)

Paper	Title	Page
MOPMF073	Rejuvenation of 7-Gev SuperKEKB Injector Linac	300
	K. Furukawa, M. Akemoto, D.A. Arakawa, Y. Arakida, H. Ego, A. Enomoto, Y. Enomoto, T. Higo, H. Honma, N. Iida, M. Ikeda, H. Kaji, K. Kakihara, T. Kamitani, H. Katagiri, M. Kawamura, M. Kurashina, S. Matsumoto, T. Matsumoto, H. Matsushita, S. Michizono, K. Mikawa, T. Miura, F. Miyahara, H. Nakajima, K. Nakao, T. Natsui, M. Nishida, Y. Ogawa, Y. Ohnishi, S. Ohsawa, F. Qiu, I. Satake, M. Satoh, Y. Seimiya, A. Shirakawa, H. Sugimura, T. Suwada, T. Takenaka, M. Tanaka, N. Toge, Y. Yano, K. Yokoyama, M. Yoshida, R. Zhang, X. Zhou KEK, Ibaraki, Japan
	KEK injector linac has delivered electrons and positrons for particle physics and photon science experiments for more than 30 years. It was upgraded for the SuperKEKB project, which aims at a 40-fold increase in luminosity over the previous project KEKB, in order to increase our understanding of flavor physics beyond the standard model of elementary particle physics. SuperKEKB energy-asymmetric electron-positron collider with its extremely high luminosity requires a high current, low emittance and low energy spread injection beam from the injector. The electron beam is generated by a new type of RF gun, that provides a much higher beam current to correspond to a large stored beam current and a short lifetime in the ring. The positron source is another major challenge that enhances the positron bunch intensity from 1 to 4 nC by increasing the positron capture efficiency, and the positron beam emittance is reduced from 2000 μm to 10 μm in the vertical plane by introducing a damping ring, followed by the bunch compressor and energy compressor. The summary of the rejuvenation is reported.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF073
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MOPML034	Development Status of Superconducting RF Transmission Electron Microscope	481
	N. Higashi, A. Enomoto, Y. Funahashi, T. Furuya, X.J. Jin, Y. Kamiya, S. Michizono, F. Qiu, M. Yamamoto KEK, Ibaraki, Japan S. Yamashita University of Tokyo, Tokyo, Japan
	Now we are developing a new type of transmission electron microscope (TEM) employing the accelerator technologies. In place of a DC thermal gun generally used in conventional TEMs, we apply a photocathode gun and a special-shaped superconducting cavity, named two-mode cavity. The two-mode cavity has two resonant modes of TM010 (1.3 GHz) and TM020 (2.6 GHz). To superimpose these, we can suppress the increase of the energy spread, which is needed for the high-spatial-resolution TEMs. We have already developed some prototypes of the photocathode gun and two-mode cavity, and now in the middle of the performance tests. In this presentation, we will show the latest status of the development.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPML034
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WEPAK016	RF Monitor System for SuperKEKB Injector Linac	2128
	H. Katagiri, M. Akemoto, D.A. Arakawa, T. Matsumoto, T. Miura, F. Qiu, Y. Yano KEK, Ibaraki, Japan
	A new radio frequency (RF) monitor system for the SuperKEKB project has been developed at the KEK in-jector linac. The RF monitor unit, which consists of an analog I/Q demodulator, ADC/DAC board, and FPGA board achieved 50-Hz data acquisition and beam mode identification. On the RF monitor, the amplitude and phase measurement precision has achieved 0.1% rms and 0.1° rms, respectively. Sixty RF monitor units have been installed in the linac. The present status of the RF monitor system will be re-ported.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAK016
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WEPAK017	Low-level RF System for the SuperKEKB Injector LINAC	2131
	T. Matsumoto, M. Akemoto, D.A. Arakawa, H. Katagiri, T. Miura, F. Qiu, Y. Yano KEK, Ibaraki, Japan M. Akemoto, T. Miura, F. Qiu Sokendai, Ibaraki, Japan
	The low-level RF (LLRF) system of the KEK injector linac has been upgraded for the SuperKEKB. As a major change, a low-emittance and high-current RF gun was installed to satisfy 40-times higher luminosity at the SuperKEKB. In order to balance the stable RF gun operation and the electron/positron beam acceleration, the phase shifter is developed and the configuration of main drive system in the LLRF system is modified. The present status and future plan of the LLRF system upgraded for the SuperKEKB will be reported.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAK017
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WEPAK018	LLRF Control Unit for SuperKEKB Injector Linac	2134
	T. Miura, M. Akemoto, D.A. Arakawa, H. Katagiri, T. Matsumoto, F. Qiu, Y. Yano KEK, Ibaraki, Japan N. Liu Sokendai, Ibaraki, Japan
	The low-level RF (LLRF) control unit based on the digital system has been developed for a stable and high precision pulse modulation for the SuperKEKB. The RF pulse is changed at a 50-Hz repetition rate for the top-up injection to four different rings by the event system. The LLRF control unit has not only the pulse modulator, but also other functions: VSWR meter, RF monitor, event receiver (EVR), and pulse-shortening detection.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAK018
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WEPAL017	Adaptive Feedforward Control Design Based on Simulink for the J-PARC LINAC LLRF System	2187
	S. Li J-PARC, KEK & JAEA, Ibaraki-ken, Japan Z. Fang, Y. Fukui, K. Futatsukawa, F. Qiu KEK, Ibaraki, Japan S. Mizobata, Y. Sato, S. Shinozaki JAEA/J-PARC, Tokai-mura, Japan
	In j-parc linac, for dealing with high beam loading effect, an adaptive feedforward control method which based on iterative learning control was put forward. At the same time, in order to verify its effectiveness before it is officially put into use, an llrf system simulation model was built in simulink, matlab. In this paper, the architecture of llrf system simulation model will be introduced. The result of iterative learning control (ILC) is summarized.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL017
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THPML073	Measurement of the RF Reference Phase Stability in the SuperKEKB Injector LINAC	4815
SUSPL063	use link to see paper's listing under its alternate paper code
	N. Liu Sokendai, Ibaraki, Japan D.A. Arakawa, H. Katagiri, T. Matsumoto, S. Michizono, T. Miura, F. Qiu, Y. Yano KEK, Ibaraki, Japan
	The SuperKEKB injector is a more than 600 m J-shaped LINAC. The requirement of the RF phase refer-ence stability is 0.1 degree (RMS) at 2856 MHz for SuperKEKB PHASE-2 commissioning. In order to clari-fy and improve the reference line performance, the RF reference phase stability is measured. The phase noise of the RF reference at each sector is shown in this paper. A new phase monitor system is implemented to measure the short-term stability and long-term drift due to the temperature and humidity fluctuations in the klystron gallery.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML073
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Paper

Title

Page

Rejuvenation of 7-Gev SuperKEKB Injector Linac

300

K. Furukawa, M. Akemoto, D.A. Arakawa, Y. Arakida, H. Ego, A. Enomoto, Y. Enomoto, T. Higo, H. Honma, N. Iida, M. Ikeda, H. Kaji, K. Kakihara, T. Kamitani, H. Katagiri, M. Kawamura, M. Kurashina, S. Matsumoto, T. Matsumoto, H. Matsushita, S. Michizono, K. Mikawa, T. Miura, F. Miyahara, H. Nakajima, K. Nakao, T. Natsui, M. Nishida, Y. Ogawa, Y. Ohnishi, S. Ohsawa, F. Qiu, I. Satake, M. Satoh, Y. Seimiya, A. Shirakawa, H. Sugimura, T. Suwada, T. Takenaka, M. Tanaka, N. Toge, Y. Yano, K. Yokoyama, M. Yoshida, R. Zhang, X. Zhou
KEK, Ibaraki, Japan

KEK injector linac has delivered electrons and positrons for particle physics and photon science experiments for more than 30 years. It was upgraded for the SuperKEKB project, which aims at a 40-fold increase in luminosity over the previous project KEKB, in order to increase our understanding of flavor physics beyond the standard model of elementary particle physics. SuperKEKB energy-asymmetric electron-positron collider with its extremely high luminosity requires a high current, low emittance and low energy spread injection beam from the injector. The electron beam is generated by a new type of RF gun, that provides a much higher beam current to correspond to a large stored beam current and a short lifetime in the ring. The positron source is another major challenge that enhances the positron bunch intensity from 1 to 4 nC by increasing the positron capture efficiency, and the positron beam emittance is reduced from 2000 μm to 10 μm in the vertical plane by introducing a damping ring, followed by the bunch compressor and energy compressor. The summary of the rejuvenation is reported.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPMF073

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MOPML034

Development Status of Superconducting RF Transmission Electron Microscope

481

N. Higashi, A. Enomoto, Y. Funahashi, T. Furuya, X.J. Jin, Y. Kamiya, S. Michizono, F. Qiu, M. Yamamoto
KEK, Ibaraki, Japan
S. Yamashita
University of Tokyo, Tokyo, Japan

Now we are developing a new type of transmission electron microscope (TEM) employing the accelerator technologies. In place of a DC thermal gun generally used in conventional TEMs, we apply a photocathode gun and a special-shaped superconducting cavity, named two-mode cavity. The two-mode cavity has two resonant modes of TM010 (1.3 GHz) and TM020 (2.6 GHz). To superimpose these, we can suppress the increase of the energy spread, which is needed for the high-spatial-resolution TEMs. We have already developed some prototypes of the photocathode gun and two-mode cavity, and now in the middle of the performance tests. In this presentation, we will show the latest status of the development.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-MOPML034

Export •

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

WEPAK016

RF Monitor System for SuperKEKB Injector Linac

2128

H. Katagiri, M. Akemoto, D.A. Arakawa, T. Matsumoto, T. Miura, F. Qiu, Y. Yano
KEK, Ibaraki, Japan

A new radio frequency (RF) monitor system for the SuperKEKB project has been developed at the KEK in-jector linac. The RF monitor unit, which consists of an analog I/Q demodulator, ADC/DAC board, and FPGA board achieved 50-Hz data acquisition and beam mode identification. On the RF monitor, the amplitude and phase measurement precision has achieved 0.1% rms and 0.1° rms, respectively. Sixty RF monitor units have been installed in the linac. The present status of the RF monitor system will be re-ported.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAK016

Export •

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

WEPAK017

Low-level RF System for the SuperKEKB Injector LINAC

2131

T. Matsumoto, M. Akemoto, D.A. Arakawa, H. Katagiri, T. Miura, F. Qiu, Y. Yano
KEK, Ibaraki, Japan
M. Akemoto, T. Miura, F. Qiu
Sokendai, Ibaraki, Japan

The low-level RF (LLRF) system of the KEK injector linac has been upgraded for the SuperKEKB. As a major change, a low-emittance and high-current RF gun was installed to satisfy 40-times higher luminosity at the SuperKEKB. In order to balance the stable RF gun operation and the electron/positron beam acceleration, the phase shifter is developed and the configuration of main drive system in the LLRF system is modified. The present status and future plan of the LLRF system upgraded for the SuperKEKB will be reported.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAK017

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

WEPAK018

LLRF Control Unit for SuperKEKB Injector Linac

2134

T. Miura, M. Akemoto, D.A. Arakawa, H. Katagiri, T. Matsumoto, F. Qiu, Y. Yano
KEK, Ibaraki, Japan
N. Liu
Sokendai, Ibaraki, Japan

The low-level RF (LLRF) control unit based on the digital system has been developed for a stable and high precision pulse modulation for the SuperKEKB. The RF pulse is changed at a 50-Hz repetition rate for the top-up injection to four different rings by the event system. The LLRF control unit has not only the pulse modulator, but also other functions: VSWR meter, RF monitor, event receiver (EVR), and pulse-shortening detection.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAK018

Export •

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

WEPAL017

Adaptive Feedforward Control Design Based on Simulink for the J-PARC LINAC LLRF System

2187

S. Li
J-PARC, KEK & JAEA, Ibaraki-ken, Japan
Z. Fang, Y. Fukui, K. Futatsukawa, F. Qiu
KEK, Ibaraki, Japan
S. Mizobata, Y. Sato, S. Shinozaki
JAEA/J-PARC, Tokai-mura, Japan

In j-parc linac, for dealing with high beam loading effect, an adaptive feedforward control method which based on iterative learning control was put forward. At the same time, in order to verify its effectiveness before it is officially put into use, an llrf system simulation model was built in simulink, matlab. In this paper, the architecture of llrf system simulation model will be introduced. The result of iterative learning control (ILC) is summarized.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-WEPAL017

Export •

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

THPML073

Measurement of the RF Reference Phase Stability in the SuperKEKB Injector LINAC

4815

SUSPL063

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

N. Liu
Sokendai, Ibaraki, Japan
D.A. Arakawa, H. Katagiri, T. Matsumoto, S. Michizono, T. Miura, F. Qiu, Y. Yano
KEK, Ibaraki, Japan

The SuperKEKB injector is a more than 600 m J-shaped LINAC. The requirement of the RF phase refer-ence stability is 0.1 degree (RMS) at 2856 MHz for SuperKEKB PHASE-2 commissioning. In order to clari-fy and improve the reference line performance, the RF reference phase stability is measured. The phase noise of the RF reference at each sector is shown in this paper. A new phase monitor system is implemented to measure the short-term stability and long-term drift due to the temperature and humidity fluctuations in the klystron gallery.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2018-THPML073

Export •

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