LINAC2018 - Classification: Technology / RF power sources and power couplers

Paper	Title	Page
WE1A04	The High Power RF System for the European XFEL	601
	S. Choroba DESY, Hamburg, Germany
	The presentation will be on the design, construction and commissioning of the high power RF system for the European XFEL. The RF system consists of 26 high power RF stations each capable of 10MW RF pulse power. It will report on the overall system layout, cover RF system components e.g. klystrons, modulators and high power RF waveguide distribution. It will also cover system modifications during construction phase and report on commissioning results.
	Slides WE1A04 [12.620 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-WE1A04
About •	paper received ※ 17 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
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THPO090	The Analysis of Module Failure in High Solid-state Amplifier for High Current RFQ	886
	L.P. Sun, Y. He, G. Huang, C.X. Li, L. Lu, A. Shi, L.B. Shi, X.B. Xu, H.W. Zhao IMP/CAS, Lanzhou, People’s Republic of China
	New accelerator RF system was upgraded to the solid-state amplifier in ADS project due to its stable, sustainable and reliable. Until now, newest 80kW SSA was adopted in IMP, operating in 162.5MHz, and over 120 power modules were combined through several synthesizers for 80kW output. but since too many modules were optimized for amplitude and phase in the same time, one or some failure of circulator will lead to injure of whole RF system, when wavelength meets a specific condition, injure would turn out severe accident and heavy loss. In this paper, analyzing and simulating the multi-level synthetic matrix was the important method for ADS accident happened in June 20. 2017, the failure simulated results for RF amplify links under the specific circumstances also was presented simultaneously.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO090
About •	paper received ※ 17 September 2018 paper accepted ※ 31 October 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPO091	90 kW Solid-state RF Amplifier with a TE011-mode Cavity Power-combiner at 476 MHz	889
THOP07	use link to see paper's listing under its alternate paper code
	Y. Otake, T. Asaka, T. Inagaki RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan S. Aizawa, K. Nagatsuka, T. Okuyama, K. Sato, H. Yamada Nihon Koshuha Co. Ltd, Yokohama, Japan
	Solid-state RF amplifiers, which have long lifetimes and small failures, are the recent trend of reliable and stable high-power rf sources for particle accelerators. Hence, we designed a 90kW solid-state amplifier with an extreme low-loss TE011 mode cavity (Q0=100, 000) power-combiner operated at 476 MHz and a 6 us pulse width. Developing this amplifier is for replacement of an IOT rf amplifier, at the X-ray free-electron laser, SACLA. In SACLA, highly RF phase and amplitude stabilities of less than 0.02 deg. and 10^-4 in rms are necessary to stable lasing within a 10 % intensity fluctuation. The amplifier comprises a drive amplifier, a reentrant cavity rf power divider, 100 final amplifiers with a 1 kW output each and a TE011 mode cavity combiner. Water-cooling within 10 mK and a DC power supply with a noise of less than -100 dBV at 10 Hz for the amplifier is necessary to realize the previously mentioned stabilities. Based on the test results of the amplifier, the above-mentioned specifications with the extreme low-loss are promising. The amplifier also allows us to operate in pulsed and CW rfs for linacs and ring accelerators. We report the performance of the 90kW amplifier.
	Slides THPO091 [1.750 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO091
About •	paper received ※ 06 September 2018 paper accepted ※ 09 October 2018 issue date ※ 18 January 2019
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THPO092	LCLSII Fundamental Power Coupler Manufacturing Status and Lesson Learned	893
	S. Sierra, G. Garcin, Ch.L. Lievin, G. Vignette, I. Yao Leclerc TED, Velizy-Villacoublay, France M. Knaak, M. Pekeler RI Research Instruments GmbH, Bergisch Gladbach, Germany
	Thales and RI Research Instrument have manufactured and assembled half of the power couplers for the LCLSII project. This paper remains main characteristics of these coupler. It will also describe main challenges that were overcome among them, thickness of copper coating on Warm Internal Conductor at 150µm and lessons learned during the manufacturing phase of these couplers. The paper will also propose some possible optimization for a future mass production of such components and parameters which could be relevant for a better understanding link to the statistic results obtained.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO092
About •	paper received ※ 10 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019
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THPO093	Status and Results Obtained on a RF Conditioning Test Bench for 704 MHz Couplers in the Frame of ESS Project	895
	S. Sierra, Y. Amal, Ch.L. Lievin, I. Yao Leclerc TED, Velizy-Villacoublay, France M.E. Chahbazian, J.G. De_Oliveira, A.G. Goeury, L.J. Nennig, S.P. Petitjean GERAC Thales, Le Barp, France
	Thales and Gerac are developing a test bench able to make the RF conditioning of the Fundamental Power Couplers at 704 MHz in the frame of the ESS project for CEA. The status of the developments of the test bench is described including the modulator, klystron and all relative equipments. The paper will also describes the results obtained at the date of presentation.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO093
About •	paper received ※ 10 September 2018 paper accepted ※ 08 October 2018 issue date ※ 18 January 2019
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THPO095	Present Status of Capacitor-charging Power Supplies for Klystron Modulators in SuperKEKB Injector Linac	898
	M. Kawamura, M. Akemoto, S. Fukuda, H. Honma, S. Michizono, H. Nakajima, T. Natsui, T. Shidara KEK, Ibaraki, Japan H. Akikawa, O. Endo, K. Sato Nihon Koshuha Co. Ltd, Yokohama, Japan
	The capacitor-charging power supplies (CCPSs) for the klystron modulators have been developed from 2002 in the SuperKEKB injector linac. The specifications are that the output voltage is 43kV, the charging power is 30kJ/s, and the output voltage stability is 0.2%p-p. Being used in the old facility, their sizes are restricted in 480mm x 680 mm x 760mm. After various modifications, the 13 CCPSs in the linac have been operated with no fault since last October. The present status of the CCPSs, including the outlines, specifications, and the modifications against the faults, are described.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO095
About •	paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
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THPO096	Design Study of a High Efficiency Klystron for SuperKEKB Linac	901
	F. Qiu, S. Fukuda, S. Matsumoto, T. Matsumoto, T. Miura, T. Natsui KEK, Ibaraki, Japan
	The injector linear accelerator (linac) for the SuperKEKB particle accelerator requires a higher efficiency klystron than the currently used 50 MW, S-band, pulsed unit (PV3050/E3730), which operates at the same voltage, to increase the power redundancy. The efficiency is expected to improve from the currently observed 45% to more than 60%. We propose a type of high efficiency klystron using novel bunching mechanisms. The 1-D disk model based code is used for preliminary optimization of the tube parameters; these parameters are further checked by 2-D codes known as field charge interaction (FCI) and MAGIC. In this paper, the design consideration of the high efficiency klystron is presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO096
About •	paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
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THPO097	Recent Results for Study of Ceramic and Copper Plating for Power Couplers	905
	Y. Yamamoto, E. Kako, S. Michizono KEK, Ibaraki, Japan E. Cenni CEA/IRFU, Gif-sur-Yvette, France A. Four CEA/DRF/IRFU, Gif-sur-Yvette, France Y. Okii Nomura Plating Co, Ltd., Osaka, Japan
	KEK has conducted a survey to select an optimum ceramic after withdrawal by a domestic manufacturing company two years ago. For this selection, there are four important items on the properties of ceramic; that is, relative permittivity, dielectric loss tangent, surface and volume resistance, and secondary electron emission coefficient. For measurements of these parameters, five kinds of ceramic samples supplied from three companies were measured using three kinds of measurement systems. For measurement of secondary electron emission, scanning electron microscope (SEM) with beam blanking system was used. On the other hand, residual resistivity ratio (RRR) for copper plating, which is the most important item for quality control, has also been carried out while changing plating thickness and acid temperature. In this report, the recent results for these studies will be presented in detailed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO097
About •	paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
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THPO100	Development of a 1.5 GHz High-power CW Magnetron for SRF Accelerator	908
	L. Wenliang College of Engineering and Applied Sciences for Nanjing University, Nanjing, People’s Republic of China S. An, Y.J. Ke, S. Lingbin, Z. Pengjiao, L. Youchun, L. Zhao, B.Z. Zhou PLAI, Nanjing, People’s Republic of China J.Z. Li, L.P. Zhang, Hou, R. Rui ADS, Jiangsu Province, People’s Republic of China
	An 1.5 GHz, 13.5 kW CW high-power magnetron for a superconducting RF accelerator has been developed by Andesun Technology Group Co., Ltd. with Nanjing Sanle Electronic Information Industry Group Co., Ltd., in order to replace the klystron, that could reduce the power source cost to about one-third. The cavity, output power antenna and coupling door-nob have been optimized by using CST Studio. Testing results have shown that the resonance frequency and output power have met the requirements, and the efficiency of the magnetron is higher that 78.45%.
	Poster THPO100 [0.574 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO100
About •	paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
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THPO102	Design Studies of Output Window for CEPC Klystron	911
	Z.J. Lu, Y.L. Chi, S. Fukuda, G. Pei, S. Pei, S.C. Wang, O. Xiao, U. N. Zaib, Z.S. Zhou IHEP, Beijing, People’s Republic of China S. Fukuda KEK, Ibaraki, Japan
	A high power and high efficiency klystron of the 650MHz, 800kW CW klystron for the Circular Electron Positron Collider (CEPC) is designed and developed at IHEP. This paper presents the design and simulation for the high power coaxial window for it. Plan of the hot test (high power testing before installing to the klystron) are also described. Simulation software of CST, ANSYS and Multipac 2.1 are used for design of window microwave structure, thermal analysis and multipacting effects. We obtained the good simulation results successively; the coaxial window S-parameter analysis, has revealed a low reflection at the operating frequency of 650 MHz. The thermal simulation shows a good temperature distribution under the cw 800kW propagation; maximum temperature has been found to be 33 °C at ceramic with water cooling in the inner and outer conductor. The multipacting at the window is possible source of the failure and it is shown that multipacting has less chance to be happened on the surface of ceramic.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO102
About •	paper received ※ 12 September 2018 paper accepted ※ 31 October 2018 issue date ※ 18 January 2019
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THPO103	Application of Solid State Amplifiers in ADS Project at IHEP	914
	O. Xiao Institute of High Energy Physics (IHEP), People’s Republic of China Y.L. Chi, N. Gan, X. Ma, Z.S. Zhou IHEP, Beijing, People’s Republic of China
	The solid state amplifier is an important part of the RF power source system of ADS project at IHEP. Three kinds of solid state amplifier with different power and frequency have been applied. In this paper, the specifications of solid state amplifier are presented. In addition, the principle of breakdown of power modules during the high power test of coupler are analyzed.
	Poster THPO103 [0.195 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO103
About •	paper received ※ 17 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
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THPO104	Development of 150.4MHz Continuous Wave Solid-state Amplifier	917
	L. Zhao Nanjing University of Aeronautics and Astronautics, Jiangning, People’s Republic of China S. An, Y.J. Ke, Z. Pengjiao, L. Wenliang, B.Z. Zhou PLAI, Nanjing, People’s Republic of China
	A 150.4MHz to 155.4MHz, 300W continuous wave solid-state amplifier as an accelerator power source has been developed by us. In order to increase the lifetime of MOSFET and meet the requirements of every parameters, Drain voltage and quiescent current is set at a better point with a well-designed heat dissipation structure, we make the solid state amplifier stable in performance. Taking the microwave leakage into account, the chassis structure is optimized and designed, and the microwave absorption device is adopted to make the structure compact, protect other parts not affected by the microwave leakage. After the assembly is completed, the working parameters meet the design requirements very well. The MOSFET flange temperature and output parameters meet the design requirements.
	Poster THPO104 [1.405 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO104
About •	paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
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THPO107	High Power Coupler R&D for Superconducting CH-cavities	920
SPWR025	use link to see paper's listing under its alternate paper code
	J. List, K. Aulenbacher, W.A. Barth, F.D. Dziuba, V. Gettmann, T. Kürzeder, M. Miski-Oglu HIM, Mainz, Germany K. Aulenbacher IKP, Mainz, Germany W.A. Barth, M. Heilmann, J. Salvatore, A. Schnase, S. Yaramyshev GSI, Darmstadt, Germany M. Basten, M. Busch, H. Podlech, M. Schwarz IAP, Frankfurt am Main, Germany
	The upcoming demands of the future research programs at GSI exceed the technical opportunities of the existing UNIversal Linear ACcelerator (UNILAC). Besides, the machine will be exclusively used as an injector for FAIR (Facility for Antiproton and Ion Research) providing high power heavy ion beams at a low repetition rate for injection into the synchrotron. A new dedicated superconducting (sc) continuous wave (cw) Linac is crucial to keep the research program competitive. The first part of the cw-linac, comprising a 217 MHz multi gap Crossbar-H-mode (CH) cavity surrounded by two sc solenoids inside a cryostat, already served as a prototype demonstrating reliable operability in a realistic accelerator environment. A sufficient high power RF-coupling concept is needed to feed this newly developed cw-RF cavity with up to 5 kW of RF-power. A high power coupler test stand was recently built to provide for a testing environment; further upgrade measures of this test area are foreseen. This contribution deals with the recent coupler R&D for the demonstrator set up. Besides simulations of thermal losses at the coupler (inside the RF-cavity) will be shown as well.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO107
About •	paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
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Paper

Title

Page

The High Power RF System for the European XFEL

601

S. Choroba
DESY, Hamburg, Germany

The presentation will be on the design, construction and commissioning of the high power RF system for the European XFEL. The RF system consists of 26 high power RF stations each capable of 10MW RF pulse power. It will report on the overall system layout, cover RF system components e.g. klystrons, modulators and high power RF waveguide distribution. It will also cover system modifications during construction phase and report on commissioning results.

Slides WE1A04 [12.620 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-WE1A04

About •

paper received ※ 17 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

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THPO090

The Analysis of Module Failure in High Solid-state Amplifier for High Current RFQ

886

L.P. Sun, Y. He, G. Huang, C.X. Li, L. Lu, A. Shi, L.B. Shi, X.B. Xu, H.W. Zhao
IMP/CAS, Lanzhou, People’s Republic of China

New accelerator RF system was upgraded to the solid-state amplifier in ADS project due to its stable, sustainable and reliable. Until now, newest 80kW SSA was adopted in IMP, operating in 162.5MHz, and over 120 power modules were combined through several synthesizers for 80kW output. but since too many modules were optimized for amplitude and phase in the same time, one or some failure of circulator will lead to injure of whole RF system, when wavelength meets a specific condition, injure would turn out severe accident and heavy loss. In this paper, analyzing and simulating the multi-level synthetic matrix was the important method for ADS accident happened in June 20. 2017, the failure simulated results for RF amplify links under the specific circumstances also was presented simultaneously.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO090

About •

paper received ※ 17 September 2018 paper accepted ※ 31 October 2018 issue date ※ 18 January 2019

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THPO091

90 kW Solid-state RF Amplifier with a TE011-mode Cavity Power-combiner at 476 MHz

889

THOP07

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

Y. Otake, T. Asaka, T. Inagaki
RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
S. Aizawa, K. Nagatsuka, T. Okuyama, K. Sato, H. Yamada
Nihon Koshuha Co. Ltd, Yokohama, Japan

Solid-state RF amplifiers, which have long lifetimes and small failures, are the recent trend of reliable and stable high-power rf sources for particle accelerators. Hence, we designed a 90kW solid-state amplifier with an extreme low-loss TE011 mode cavity (Q0=100, 000) power-combiner operated at 476 MHz and a 6 us pulse width. Developing this amplifier is for replacement of an IOT rf amplifier, at the X-ray free-electron laser, SACLA. In SACLA, highly RF phase and amplitude stabilities of less than 0.02 deg. and 10^-4 in rms are necessary to stable lasing within a 10 % intensity fluctuation. The amplifier comprises a drive amplifier, a reentrant cavity rf power divider, 100 final amplifiers with a 1 kW output each and a TE011 mode cavity combiner. Water-cooling within 10 mK and a DC power supply with a noise of less than -100 dBV at 10 Hz for the amplifier is necessary to realize the previously mentioned stabilities. Based on the test results of the amplifier, the above-mentioned specifications with the extreme low-loss are promising. The amplifier also allows us to operate in pulsed and CW rfs for linacs and ring accelerators. We report the performance of the 90kW amplifier.

Slides THPO091 [1.750 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO091

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paper received ※ 06 September 2018 paper accepted ※ 09 October 2018 issue date ※ 18 January 2019

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THPO092

LCLSII Fundamental Power Coupler Manufacturing Status and Lesson Learned

893

S. Sierra, G. Garcin, Ch.L. Lievin, G. Vignette, I. Yao Leclerc
TED, Velizy-Villacoublay, France
M. Knaak, M. Pekeler
RI Research Instruments GmbH, Bergisch Gladbach, Germany

Thales and RI Research Instrument have manufactured and assembled half of the power couplers for the LCLSII project. This paper remains main characteristics of these coupler. It will also describe main challenges that were overcome among them, thickness of copper coating on Warm Internal Conductor at 150µm and lessons learned during the manufacturing phase of these couplers. The paper will also propose some possible optimization for a future mass production of such components and parameters which could be relevant for a better understanding link to the statistic results obtained.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO092

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paper received ※ 10 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019

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THPO093

Status and Results Obtained on a RF Conditioning Test Bench for 704 MHz Couplers in the Frame of ESS Project

895

S. Sierra, Y. Amal, Ch.L. Lievin, I. Yao Leclerc
TED, Velizy-Villacoublay, France
M.E. Chahbazian, J.G. De_Oliveira, A.G. Goeury, L.J. Nennig, S.P. Petitjean
GERAC Thales, Le Barp, France

Thales and Gerac are developing a test bench able to make the RF conditioning of the Fundamental Power Couplers at 704 MHz in the frame of the ESS project for CEA. The status of the developments of the test bench is described including the modulator, klystron and all relative equipments. The paper will also describes the results obtained at the date of presentation.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO093

About •

paper received ※ 10 September 2018 paper accepted ※ 08 October 2018 issue date ※ 18 January 2019

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THPO095

Present Status of Capacitor-charging Power Supplies for Klystron Modulators in SuperKEKB Injector Linac

898

M. Kawamura, M. Akemoto, S. Fukuda, H. Honma, S. Michizono, H. Nakajima, T. Natsui, T. Shidara
KEK, Ibaraki, Japan
H. Akikawa, O. Endo, K. Sato
Nihon Koshuha Co. Ltd, Yokohama, Japan

The capacitor-charging power supplies (CCPSs) for the klystron modulators have been developed from 2002 in the SuperKEKB injector linac. The specifications are that the output voltage is 43kV, the charging power is 30kJ/s, and the output voltage stability is 0.2%p-p. Being used in the old facility, their sizes are restricted in 480mm x 680 mm x 760mm. After various modifications, the 13 CCPSs in the linac have been operated with no fault since last October. The present status of the CCPSs, including the outlines, specifications, and the modifications against the faults, are described.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO095

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paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

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THPO096

Design Study of a High Efficiency Klystron for SuperKEKB Linac

901

F. Qiu, S. Fukuda, S. Matsumoto, T. Matsumoto, T. Miura, T. Natsui
KEK, Ibaraki, Japan

The injector linear accelerator (linac) for the SuperKEKB particle accelerator requires a higher efficiency klystron than the currently used 50 MW, S-band, pulsed unit (PV3050/E3730), which operates at the same voltage, to increase the power redundancy. The efficiency is expected to improve from the currently observed 45% to more than 60%. We propose a type of high efficiency klystron using novel bunching mechanisms. The 1-D disk model based code is used for preliminary optimization of the tube parameters; these parameters are further checked by 2-D codes known as field charge interaction (FCI) and MAGIC. In this paper, the design consideration of the high efficiency klystron is presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO096

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paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

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

THPO097

Recent Results for Study of Ceramic and Copper Plating for Power Couplers

905

Y. Yamamoto, E. Kako, S. Michizono
KEK, Ibaraki, Japan
E. Cenni
CEA/IRFU, Gif-sur-Yvette, France
A. Four
CEA/DRF/IRFU, Gif-sur-Yvette, France
Y. Okii
Nomura Plating Co, Ltd., Osaka, Japan

KEK has conducted a survey to select an optimum ceramic after withdrawal by a domestic manufacturing company two years ago. For this selection, there are four important items on the properties of ceramic; that is, relative permittivity, dielectric loss tangent, surface and volume resistance, and secondary electron emission coefficient. For measurements of these parameters, five kinds of ceramic samples supplied from three companies were measured using three kinds of measurement systems. For measurement of secondary electron emission, scanning electron microscope (SEM) with beam blanking system was used. On the other hand, residual resistivity ratio (RRR) for copper plating, which is the most important item for quality control, has also been carried out while changing plating thickness and acid temperature. In this report, the recent results for these studies will be presented in detailed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO097

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paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

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THPO100

Development of a 1.5 GHz High-power CW Magnetron for SRF Accelerator

908

L. Wenliang
College of Engineering and Applied Sciences for Nanjing University, Nanjing, People’s Republic of China
S. An, Y.J. Ke, S. Lingbin, Z. Pengjiao, L. Youchun, L. Zhao, B.Z. Zhou
PLAI, Nanjing, People’s Republic of China
J.Z. Li, L.P. Zhang, Hou, R. Rui
ADS, Jiangsu Province, People’s Republic of China

An 1.5 GHz, 13.5 kW CW high-power magnetron for a superconducting RF accelerator has been developed by Andesun Technology Group Co., Ltd. with Nanjing Sanle Electronic Information Industry Group Co., Ltd., in order to replace the klystron, that could reduce the power source cost to about one-third. The cavity, output power antenna and coupling door-nob have been optimized by using CST Studio. Testing results have shown that the resonance frequency and output power have met the requirements, and the efficiency of the magnetron is higher that 78.45%.

Poster THPO100 [0.574 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO100

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paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

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THPO102

Design Studies of Output Window for CEPC Klystron

911

Z.J. Lu, Y.L. Chi, S. Fukuda, G. Pei, S. Pei, S.C. Wang, O. Xiao, U. N. Zaib, Z.S. Zhou
IHEP, Beijing, People’s Republic of China
S. Fukuda
KEK, Ibaraki, Japan

A high power and high efficiency klystron of the 650MHz, 800kW CW klystron for the Circular Electron Positron Collider (CEPC) is designed and developed at IHEP. This paper presents the design and simulation for the high power coaxial window for it. Plan of the hot test (high power testing before installing to the klystron) are also described. Simulation software of CST, ANSYS and Multipac 2.1 are used for design of window microwave structure, thermal analysis and multipacting effects. We obtained the good simulation results successively; the coaxial window S-parameter analysis, has revealed a low reflection at the operating frequency of 650 MHz. The thermal simulation shows a good temperature distribution under the cw 800kW propagation; maximum temperature has been found to be 33 °C at ceramic with water cooling in the inner and outer conductor. The multipacting at the window is possible source of the failure and it is shown that multipacting has less chance to be happened on the surface of ceramic.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO102

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paper received ※ 12 September 2018 paper accepted ※ 31 October 2018 issue date ※ 18 January 2019

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THPO103

Application of Solid State Amplifiers in ADS Project at IHEP

914

O. Xiao
Institute of High Energy Physics (IHEP), People’s Republic of China
Y.L. Chi, N. Gan, X. Ma, Z.S. Zhou
IHEP, Beijing, People’s Republic of China

The solid state amplifier is an important part of the RF power source system of ADS project at IHEP. Three kinds of solid state amplifier with different power and frequency have been applied. In this paper, the specifications of solid state amplifier are presented. In addition, the principle of breakdown of power modules during the high power test of coupler are analyzed.

Poster THPO103 [0.195 MB]

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reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO103

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paper received ※ 17 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

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THPO104

Development of 150.4MHz Continuous Wave Solid-state Amplifier

917

L. Zhao
Nanjing University of Aeronautics and Astronautics, Jiangning, People’s Republic of China
S. An, Y.J. Ke, Z. Pengjiao, L. Wenliang, B.Z. Zhou
PLAI, Nanjing, People’s Republic of China

A 150.4MHz to 155.4MHz, 300W continuous wave solid-state amplifier as an accelerator power source has been developed by us. In order to increase the lifetime of MOSFET and meet the requirements of every parameters, Drain voltage and quiescent current is set at a better point with a well-designed heat dissipation structure, we make the solid state amplifier stable in performance. Taking the microwave leakage into account, the chassis structure is optimized and designed, and the microwave absorption device is adopted to make the structure compact, protect other parts not affected by the microwave leakage. After the assembly is completed, the working parameters meet the design requirements very well. The MOSFET flange temperature and output parameters meet the design requirements.

Poster THPO104 [1.405 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO104

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paper received ※ 12 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

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THPO107

High Power Coupler R&D for Superconducting CH-cavities

920

SPWR025

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

J. List, K. Aulenbacher, W.A. Barth, F.D. Dziuba, V. Gettmann, T. Kürzeder, M. Miski-Oglu
HIM, Mainz, Germany
K. Aulenbacher
IKP, Mainz, Germany
W.A. Barth, M. Heilmann, J. Salvatore, A. Schnase, S. Yaramyshev
GSI, Darmstadt, Germany
M. Basten, M. Busch, H. Podlech, M. Schwarz
IAP, Frankfurt am Main, Germany

The upcoming demands of the future research programs at GSI exceed the technical opportunities of the existing UNIversal Linear ACcelerator (UNILAC). Besides, the machine will be exclusively used as an injector for FAIR (Facility for Antiproton and Ion Research) providing high power heavy ion beams at a low repetition rate for injection into the synchrotron. A new dedicated superconducting (sc) continuous wave (cw) Linac is crucial to keep the research program competitive. The first part of the cw-linac, comprising a 217 MHz multi gap Crossbar-H-mode (CH) cavity surrounded by two sc solenoids inside a cryostat, already served as a prototype demonstrating reliable operability in a realistic accelerator environment. A sufficient high power RF-coupling concept is needed to feed this newly developed cw-RF cavity with up to 5 kW of RF-power. A high power coupler test stand was recently built to provide for a testing environment; further upgrade measures of this test area are foreseen. This contribution deals with the recent coupler R&D for the demonstrator set up. Besides simulations of thermal losses at the coupler (inside the RF-cavity) will be shown as well.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-THPO107

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paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

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