IPAC2017 - List of Authors (Maesaka, H.)

Paper	Title	Page
TUOAA2	A Soft X-Ray Free-Electron Laser Beamline of SACLA	1209
	K. Togawa, T. Asaka, N. Azumi, T. Hara, T. Hasegawa, N. Hosoda, T. Inagaki, T. Ishikawa, R. Kinjo, C. Kondo, H. Maesaka, S. Matsui, T. Ohshima, Y. Otake, S. Owada, H. Tanaka, T. Tanaka, M. Yabashi RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan T. Bizen, H. Kimura, S. Matsubara, K. Nakajima, T. Sakurai, T. Togashi, K. Tono JASRI/SPring-8, Hyogo, Japan T. Fukui RIKEN SPring-8 Center, Innovative Light Sources Division, Hyogo, Japan
	At the Japanese x-ray free-electron laser (FEL) facility, SACLA, the beamline-1 has been upgraded from a spontaneous radiation to a soft x-ray FEL beamline, which generates FEL lights over a wide wavelength range from the extreme-ultraviolet to the soft x-ray regions. We started operation for users in July 2016. A dedicated accelerator, which is a refinement of the SCSS test accelerator operated in 2005-2013, was installed beside the XFEL beamlines in the SACLA undulator hall. The SCSS concept to make an FEL facility compact was continuously adopted. In the 2016 summer shutdown period, the beam energy was upgraded from 500 MeV to 800 MeV by adding two C-band rf units. The maximum K-value of the undulator magnet is 2.1. The available wavelengths of the FEL lights were extended to the range from 8 to 50 nm with pulse energies between a few to few tensμJ at an operational repetition rate of 60 Hz. In this conference, we will report an overview of the upgraded SACLA-beamline-1 and characteristics of the FEL light pulse.
	Slides TUOAA2 [15.457 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUOAA2
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THPAB117	Development of a New LLRF System Based on MicroTCA.4 for the SPring-8 Storage Ring	3996
	T. Ohshima, H. Ego, N. Hosoda, H. Maesaka RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan T. Fukui RIKEN SPring-8 Center, Innovative Light Sources Division, Hyogo, Japan M. Ishii JASRI/SPring-8, Hyogo-ken, Japan
	SPring-8 is a 3rd generation synchrotron radiation facility, which has been operated since 1997. The analog-circuit-based rf modules now in use at the storage ring are obsolete and hard to be maintained. The renewal of them with modern digital ones is underway and the developed LLRF system will be used for the operation of SPring-8-II. We built an amplitude and phase stabilizing system with commercial MicroTCA.4 modules. A motor driver controlled through EtherCAT was newly adapted to the cavity tuner. The system was implemented to the high power rf test stand which consists of a 1 MW klystron, a circulator, and a 508.58 MHz cavity. The rf power was successfully regulated to keep the cavity voltage with an amplitude deviation of less than 0.1% and a phase stability of less than 0.1 degree in rms. We are also developing new MTCA.4 modules: a digitizer AMC having sampling rate of 370 MHz and 16bit resolution, and a signal conditioning RTM. These modules are used for under-sampling rf detection achieving simple composition and more robustness to the ambient parameter changes. We will start installation of the digital system to one of four rf stations in the storage ring in summer 2017.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB117
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MOPAB066	Development and Performance Test of the BPM System for the SPring-8 Upgrade	265
	H. Maesaka RIKEN SPring-8 Center, Innovative Light Sources Division, Hyogo, Japan H. Dewa, T. Fujita, M. Masaki JASRI, Hyogo, Japan S. Takano Japan Synchrotron Radiation Research Institute (JASRI), RIKEN SPring-8 Center, Hyogo, Japan
	We are developing a stable and precise BPM system for the low-emittance upgrade of SPring-8. One of the essential requirements for the BPM is the long term stabilization of the photon beam by regulating the electron beam orbit. Both the single-pass resolution of 100 um rms for an injected beam charge of 100 pC and an accuracy of 100 um rms are also crucial for beam commissioning. Drift sources of the present BPM system have been investigated extensively, such as humidity-dependent drifts coming from the radiation damage of coaxial cables, and the results are fed back to the design of the new BPM system. We have optimized the design of the button BPM electrodes to reconcile reduction of trapped-mode heating and maximization of the signal intensity. Stringent machining tolerance is imposed on a BPM head to align the BPM electric center accurately. A few kinds of the BPM head prototypes were produced and the machining accuracy, RF characteristics etc. were confirmed to be sufficient. We have installed one of the prototypes in the present storage ring to test the performance of the new BPM system under development, and have been obtaining successful results satisfying the requirements.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB066
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Paper

Title

Page

A Soft X-Ray Free-Electron Laser Beamline of SACLA

1209

K. Togawa, T. Asaka, N. Azumi, T. Hara, T. Hasegawa, N. Hosoda, T. Inagaki, T. Ishikawa, R. Kinjo, C. Kondo, H. Maesaka, S. Matsui, T. Ohshima, Y. Otake, S. Owada, H. Tanaka, T. Tanaka, M. Yabashi
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
T. Bizen, H. Kimura, S. Matsubara, K. Nakajima, T. Sakurai, T. Togashi, K. Tono
JASRI/SPring-8, Hyogo, Japan
T. Fukui
RIKEN SPring-8 Center, Innovative Light Sources Division, Hyogo, Japan

At the Japanese x-ray free-electron laser (FEL) facility, SACLA, the beamline-1 has been upgraded from a spontaneous radiation to a soft x-ray FEL beamline, which generates FEL lights over a wide wavelength range from the extreme-ultraviolet to the soft x-ray regions. We started operation for users in July 2016. A dedicated accelerator, which is a refinement of the SCSS test accelerator operated in 2005-2013, was installed beside the XFEL beamlines in the SACLA undulator hall. The SCSS concept to make an FEL facility compact was continuously adopted. In the 2016 summer shutdown period, the beam energy was upgraded from 500 MeV to 800 MeV by adding two C-band rf units. The maximum K-value of the undulator magnet is 2.1. The available wavelengths of the FEL lights were extended to the range from 8 to 50 nm with pulse energies between a few to few tensμJ at an operational repetition rate of 60 Hz. In this conference, we will report an overview of the upgraded SACLA-beamline-1 and characteristics of the FEL light pulse.

Slides TUOAA2 [15.457 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-TUOAA2

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THPAB117

Development of a New LLRF System Based on MicroTCA.4 for the SPring-8 Storage Ring

3996

T. Ohshima, H. Ego, N. Hosoda, H. Maesaka
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
T. Fukui
RIKEN SPring-8 Center, Innovative Light Sources Division, Hyogo, Japan
M. Ishii
JASRI/SPring-8, Hyogo-ken, Japan

SPring-8 is a 3rd generation synchrotron radiation facility, which has been operated since 1997. The analog-circuit-based rf modules now in use at the storage ring are obsolete and hard to be maintained. The renewal of them with modern digital ones is underway and the developed LLRF system will be used for the operation of SPring-8-II. We built an amplitude and phase stabilizing system with commercial MicroTCA.4 modules. A motor driver controlled through EtherCAT was newly adapted to the cavity tuner. The system was implemented to the high power rf test stand which consists of a 1 MW klystron, a circulator, and a 508.58 MHz cavity. The rf power was successfully regulated to keep the cavity voltage with an amplitude deviation of less than 0.1% and a phase stability of less than 0.1 degree in rms. We are also developing new MTCA.4 modules: a digitizer AMC having sampling rate of 370 MHz and 16bit resolution, and a signal conditioning RTM. These modules are used for under-sampling rf detection achieving simple composition and more robustness to the ambient parameter changes. We will start installation of the digital system to one of four rf stations in the storage ring in summer 2017.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-THPAB117

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

MOPAB066

Development and Performance Test of the BPM System for the SPring-8 Upgrade

265

H. Maesaka
RIKEN SPring-8 Center, Innovative Light Sources Division, Hyogo, Japan
H. Dewa, T. Fujita, M. Masaki
JASRI, Hyogo, Japan
S. Takano
Japan Synchrotron Radiation Research Institute (JASRI), RIKEN SPring-8 Center, Hyogo, Japan

We are developing a stable and precise BPM system for the low-emittance upgrade of SPring-8. One of the essential requirements for the BPM is the long term stabilization of the photon beam by regulating the electron beam orbit. Both the single-pass resolution of 100 um rms for an injected beam charge of 100 pC and an accuracy of 100 um rms are also crucial for beam commissioning. Drift sources of the present BPM system have been investigated extensively, such as humidity-dependent drifts coming from the radiation damage of coaxial cables, and the results are fed back to the design of the new BPM system. We have optimized the design of the button BPM electrodes to reconcile reduction of trapped-mode heating and maximization of the signal intensity. Stringent machining tolerance is imposed on a BPM head to align the BPM electric center accurately. A few kinds of the BPM head prototypes were produced and the machining accuracy, RF characteristics etc. were confirmed to be sufficient. We have installed one of the prototypes in the present storage ring to test the performance of the new BPM system under development, and have been obtaining successful results satisfying the requirements.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-MOPAB066

Export •

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