SRF2013 - List of Keywords (feedback)

Paper	Title	Other Keywords	Page
MOP043	ILC-HiGrade Cavities as a Tool of Quality Control for European XFEL	cavity, controls, radiation, framework	212
	A. Navitski, E. Elsen, B. Foster, J. Iversen, A. Matheisen, D. Reschke, W. Singer, X. Singer, L. Steder, M. Wenskat DESY, Hamburg, Germany R. Laasch, Y. Tamashevich University of Hamburg, Hamburg, Germany
	Funding: BMBF, Helmholtz Association, ILC-HiGrade, FP7 (CRISP), Alexander von Humboldt Stiftung/Foundation The EXFEL order for SRF cavities includes 24 cavities, which are part of the ILC-HiGrade program. Initially, these cavities serve as quality control (QC) sample extracted from the EXFEL cavities series production on a regular basis. The QC and quality assurance (QA) include all processing steps of the EXFEL cavities. To maximize the information from these so-called QC cavities, a surface mapping technique is applied in a second cold RF test. There the cavities delivered have experienced identical treatment of the inner surface with the exception of mounting of the Helium vessel. After the normal acceptance test at the cavity RF measurement facility, the cavities are removed from the production flow. Further quality assurance steps beginning with a detailed RF test with surface mapping followed by a high resolution optical inspection (OBACHT) are carried out to improve the understanding of defects in close collaboration with the standing experts engaged in the EXFEL production. Results of the first QC cavities tests as well as planned further R&D will be presented and discussed.

TUIOA05	New Insights Into Quench Caused by Surface Pits in SRF Cavities	cavity, niobium, laser, SRF	378
	Y. Xie, M. Liepe Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: Work supported by NSF Career award PHY-0841213 and the Alfred P. Sloan Foundation. Surface defects such as pits have been identified as some of the main sources of limitations of srf cavity performance. A single cell cavity with 30 artificial pits in the high magnetic field region was made to gain new insight in how pits limit the cavity performance. The test of the pit cavity showed clear evidence that the edges of two of the largest radius pits transitioned into the normal conducting state at field just below the quench field of the cavity, and that the quench was indeed induced by these two pits. The pit geometrical information measured by laser confocal microscopy combined with a numerical finite element ring-type defect model will be compared with temperature mapping results. Insights about quench and non-linear rf resistances will be presented. Y. Xie, PhD thesis, Cornell University, 2013
	Slides TUIOA05 [3.101 MB]

TUP090	Thermal Simulations for the Multi-Layer Coating Model	simulation, electromagnetic-fields, superconducting-cavity, cavity	674
	F. Meng IHEP, Beijing, People's Republic of China A. Romanenko Fermilab, Batavia, USA Y. Xie Euclid TechLabs, LLC, Solon, Ohio, USA
	Thermal simulations for the multi-layer coating model has been developed based on previous work of a finite difference thermal feedback code.* RF field-attenuation formula for the multi-layer coating model has also been included.** The temperature distribution along different superconducting layers under applied magnetic fields has been calculated with various superconducting material parameters. Y. Xie et.al., "Relationship between defects pre-heating and defects size", SRF2009. *T. Kubo et.al.,"Rf field-attenuation formulae for the multilayer coating model", IPAC2013

TUP105	Investigation of the Surface Resistivity of SRF Cavities via the Heat and Srimp Program as Well as the Multi-Cell T-Map System	cavity, SRF, accelerating-gradient, electron	724
	G.M. Ge, D. Gonnella, G.H. Hoffstaetter, M. Liepe, H. Padamsee Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA F. Furuta Cornell University, Ithaca, New York, USA
	A high-sensitive temperature mapping system for multi-cell SRF cavities has been constructed at Cornell University. The resolution of the system is 1mK. Hence it’s able to detect small temperature increases when cavities reach at low accelerating gradients e.g. 3MV/m. The surface resistivity of superconductor under radio-frequency electromagnetic field can be calculated from the temperature increases. In this contribution, the surface resistance map of multi-cell SRF cavities is shown. The temperature mapping result is possible to establish a relationship between the surface resistivity and the magnetic field as well. Unlike the RF method which is average value of the surface resistance, the T-map results give local surface resistivity versus magnetic field. BCS theory assumes the surface resistivity is independent to the magnetic field. The T-map results, however, suggest that the surface resistance at high-loss region is field dependent and caused Q-slope.

THIOA01	Infrastructure, Methods and Test Results for the Testing of 800 Series Cavities for the European XFEL	cavity, coupling, operation, controls	812
	D. Reschke DESY, Hamburg, Germany
	Funding: The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no 283745 (CRISP). The main linac of the European XFEL will consist of 100 accelerator modules, i.e. 800 superconducting accelerator cavities operated at a design gradient of 23.6 MV/m. The fabrication and surface preparation of the cavities in industry is in full swing. This talk describes the infrastructure and procedures of the vertical acceptance test in the "Accelerator Module Test Facility AMTF" at DESY. The present status of the test results is given.
	Slides THIOA01 [1.998 MB]

THIOC04	Demonstration of RF Stabilities in STF 9-cell Cavities Aiming for the Near Quench Limit Operation	operation, cavity, LLRF, controls	865
	M. Omet Sokendai, Ibaraki, Japan T. Matsumoto, S. Michizono, T. Miura KEK, Ibaraki, Japan
	In preparation of ILC an operation of two superconducting cavities controlled by digital LLRF techniques at different gradients (16 MV/m, 24 MV/m) with flat flattops and a 6.4 mA beam was demonstrated, which is only possible by PkQL control (individual setting of driving power and loaded Q per cavity). The vector sum stabilities were ΔA/A = 0.009%rms and Δφ = 0.009°rms. Since in ILC the cavity gradient spread is large (31.5 MV/m±20%) the required range of loaded Q values is 3·10⁶ to 10⁷. High loaded Q operation with a 6.1 mA beam at 2·10⁷ was demonstrated. The stabilities were ΔA/A = 0.008%rms and Δφ = 0.014°rms. Furthermore a near klystron operation within 5% of saturation was performed with a 6.2 mA beam. The stabilities were ΔA/A = 0.010%rms and Δφ = 0.009°rms.
	Slides THIOC04 [1.448 MB]

THP002	Design of 3-Cell Travelling Wave Cavity for High Gradient Test	cavity, accelerating-gradient, pick-up, niobium	892
	P.V. Avrakhov, A. Kanareykin, R.A. Kostin, Y. Xie Euclid TechLabs, LLC, Solon, Ohio, USA S. Kazakov, N. Solyak, V.P. Yakovlev Fermilab, Batavia, USA
	Utilization of a superconducting traveling wave accelerating (STWA) structure with small phase advance per cell for future high energy linear colliders may provide accelerating gradient 1.2/1.4 times larger [1] than standing wave structure. However, the STWA structure requires a feedback waveguide [1]. Recent tests of 1.3 GHz model of a single-cell cavity with waveguide feedback demonstrated an accelerating gradient comparable to the gradient in a single-cell ILC-type cavity from the same manufacturer [2]. In the present paper a design for a STWA resonator with a 3-cell accelerating cavity for high gradient tests is considered. Methods to create and support the traveling wave in this structure are discussed. The results of detailed studies of the mechanical and tuning properties of the superconducting resonator with 3-cell traveling wave accelerating structure are also presented.

THP079	Improvement of the Pneumatic Frequency Tuner of the Superconducting Resonators at IUAC	controls, linac, cavity, vacuum	1107
	A. Pandey, G.K. Chaudhari, R.N. Dutt, S. Ghosh, D. Kanjilal, J. Karmakar, D.S. Mathuria, P. Patra, A. Rai, A. Roy, B.K. Sahu, S.K. Saini IUAC, New Delhi, India
	The existing phase locking scheme of the quarter wave resonators used in superconducting linear accelerator of Inter University Accelerator Centre consists of a fast (electronic) and a slow time scale (pneumatic) control. Presently, helium gas operated mechanical tuners are being used to phase lock the resonators against the master oscillator frequency and different ion beams have been accelerated and delivered to conduct experiments. The present pneumatic frequency tuner has two limitations: (a) no proportional flow control in vacuum condition (b) large hysteresis problem in the proportional valve responsible for gas flow control. Due to these limitations, the system becomes non-linear and the response time is very slow (~sec). Using the existing system, phase locking of a resonator becomes delicate and time consuming. In addition, it was found to be difficult to implement auto phase locking mechanism on the resonator. To overcome these problems and to improve the dynamics of the existing tuner, a new pneumatic tuning system has been adopted. Details of the existing tuning mechanism and the modified tuning system along with the test results will be presented in the paper.

THP081	Development of a Slow Tuner for the 162.5 MHz Superconducting Half-Wave Resonator in IMP	cavity, cryomodule, low-level-rf, controls	1115
	S. He, Y. He, Y.L. Huang, L.B. Liu, F.F. Wang, R.X. Wang, X.W. Wang, W.M. Yue, S.H. Zhang, H.W. Zhao IMP, Lanzhou, People's Republic of China
	Funding: This work is supported by Strategic Priority Research Program of CAS (XDA0302)and National Natural Science Foundation of China (91026004) Within the framework of the C-ADS project, IMP has proposed a 162.5MHz HWR Superconducting cavity for low energy section(β=0.09) of high power proton linear accelerators. A compact slow tuner has been developed for final tuning of the resonance frequency of the cavity after cooling down to operating temperature and to compensate microphonics and Lorentz force detuning. The slow tuner is driven by an external stepper motor and gear box for coarse cavity adjustment. To reduce the force requirements of the actuator, a lever arm and scissor jack mechanism have been applied. The tuner design and recent results of warm tests as the first prototype are presented.

THP085	Equipping FLASH with MTCA.4-based LLRF System	LLRF, controls, cryomodule, cavity	1126
	J. Branlard, V. Ayvazyan, L. Butkowski, M.K. Grecki, M. Hoffmann, F. Ludwig, U. Mavrič, S. Pfeiffer, K.P. Przygoda, H. Schlarb, Ch. Schmidt, H.C. Weddig DESY, Hamburg, Germany W. Cichalewski, D.R. Makowski, A. Piotrowski TUL-DMCS, Łódź, Poland K. Czuba, I. Rutkowski, D. Sikora, L. Zembala, M. Żukociński Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland I.M. Kudla NCBJ, Świerk/Otwock, Poland K. Oliwa, W. Wierba IFJ-PAN, Kraków, Poland
	The Free-Electron Laser in Hamburg (FLASH) is now equipped with a MicroTCA-based (MTCA.4) low-level radio frequency (LLRF) system, to replace the previous VME system and to serve as a test bench for the European X-ray Free Electron Laser (XFEL) LLRF system. This paper presents details on the new FLASH LLRF system setup, including installations inside the radiation prone tunnel environment. The benefits and preliminary results of the newly installed system are also given.

THP086	LLRF System Design and Performance for XFEL Cryomodules Continuous Wave Operation	operation, cavity, LLRF, cryomodule	1129
	J. Branlard, V. Ayvazyan, L. Butkowski, K.P. Przygoda, H. Schlarb, J.K. Sekutowicz DESY, Hamburg, Germany W. Cichalewski, A. Piotrowski TUL-DMCS, Łódź, Poland W. Jałmużna Embedded Integrated Control Systems GmbH, Hamburg, Germany J. Szewiński NCBJ, Świerk/Otwock, Poland
	The Cryomodule Test Bench (CMTB) at DESY is equipped with a 100 kW Inductive Output Tube (IOT) allowing the test of superconducting cryomodules in continuous wave (CW) operation mode. Although significantly different from the nominal pulsed operation mode of the European X-Ray Free Electron Laser (XFEL), CW operation can be handled by the same Low-level Radio Frequency (LLRF) system, within minor firmware modifications. The hardware details of the LLRF setup at CMTB, the firmware and software architecture and performance results from the last CW test are presented in this contribution.

THP089	Design of LLRF System for RAON	LLRF, controls, FPGA, target	1135
	H. Do, O.R. Choi, J. Han, J.-W. Kim IBS, Daejeon, Republic of Korea C.K. Hwang KAERI, Daejon, Republic of Korea
	The low-level RF (LLRF) system being designed for RAON will allow research in the rare isotope beam facility. The LLRF system is used to feed the superconducting quarter-wave resonator having the frequency of 81.25 MHz with controlled the amplitude and phase of RF. The LLRF system uses a field programmable gate array (FPGA) to provide controlled RF amplitude and phase with ±1° and less than ±1% of stabilities, respectively. The resolution and working range is 0.004 dB and 20 dB in amplitude, respectively, and 0.5° and 360° in phase. For the RF performance test, a prototype of LLRF system is designed and fabricated. This paper will describe the design detail. Also, testing results of the prototype of LLRF system are presented.

Paper

Title

Other Keywords

Page

MOP043

ILC-HiGrade Cavities as a Tool of Quality Control for European XFEL

cavity, controls, radiation, framework

212

A. Navitski, E. Elsen, B. Foster, J. Iversen, A. Matheisen, D. Reschke, W. Singer, X. Singer, L. Steder, M. Wenskat
DESY, Hamburg, Germany
R. Laasch, Y. Tamashevich
University of Hamburg, Hamburg, Germany

Funding: BMBF, Helmholtz Association, ILC-HiGrade, FP7 (CRISP), Alexander von Humboldt Stiftung/Foundation
The EXFEL order for SRF cavities includes 24 cavities, which are part of the ILC-HiGrade program. Initially, these cavities serve as quality control (QC) sample extracted from the EXFEL cavities series production on a regular basis. The QC and quality assurance (QA) include all processing steps of the EXFEL cavities. To maximize the information from these so-called QC cavities, a surface mapping technique is applied in a second cold RF test. There the cavities delivered have experienced identical treatment of the inner surface with the exception of mounting of the Helium vessel. After the normal acceptance test at the cavity RF measurement facility, the cavities are removed from the production flow. Further quality assurance steps beginning with a detailed RF test with surface mapping followed by a high resolution optical inspection (OBACHT) are carried out to improve the understanding of defects in close collaboration with the standing experts engaged in the EXFEL production. Results of the first QC cavities tests as well as planned further R&D will be presented and discussed.

TUIOA05

New Insights Into Quench Caused by Surface Pits in SRF Cavities

cavity, niobium, laser, SRF

378

Y. Xie, M. Liepe
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: Work supported by NSF Career award PHY-0841213 and the Alfred P. Sloan Foundation.
Surface defects such as pits have been identified as some of the main sources of limitations of srf cavity performance. A single cell cavity with 30 artificial pits in the high magnetic field region was made to gain new insight in how pits limit the cavity performance*. The test of the pit cavity showed clear evidence that the edges of two of the largest radius pits transitioned into the normal conducting state at field just below the quench field of the cavity, and that the quench was indeed induced by these two pits. The pit geometrical information measured by laser confocal microscopy combined with a numerical finite element ring-type defect model will be compared with temperature mapping results. Insights about quench and non-linear rf resistances will be presented.
*Y. Xie, PhD thesis, Cornell University, 2013

Slides TUIOA05 [3.101 MB]

TUP090

Thermal Simulations for the Multi-Layer Coating Model

simulation, electromagnetic-fields, superconducting-cavity, cavity

674

F. Meng
IHEP, Beijing, People's Republic of China
A. Romanenko
Fermilab, Batavia, USA
Y. Xie
Euclid TechLabs, LLC, Solon, Ohio, USA

Thermal simulations for the multi-layer coating model has been developed based on previous work of a finite difference thermal feedback code.* RF field-attenuation formula for the multi-layer coating model has also been included.** The temperature distribution along different superconducting layers under applied magnetic fields has been calculated with various superconducting material parameters.
*Y. Xie et.al., "Relationship between defects pre-heating and defects size", SRF2009.
**T. Kubo et.al.,"Rf field-attenuation formulae for the multilayer coating model", IPAC2013

TUP105

Investigation of the Surface Resistivity of SRF Cavities via the Heat and Srimp Program as Well as the Multi-Cell T-Map System

cavity, SRF, accelerating-gradient, electron

724

G.M. Ge, D. Gonnella, G.H. Hoffstaetter, M. Liepe, H. Padamsee
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
F. Furuta
Cornell University, Ithaca, New York, USA

A high-sensitive temperature mapping system for multi-cell SRF cavities has been constructed at Cornell University. The resolution of the system is 1mK. Hence it’s able to detect small temperature increases when cavities reach at low accelerating gradients e.g. 3MV/m. The surface resistivity of superconductor under radio-frequency electromagnetic field can be calculated from the temperature increases. In this contribution, the surface resistance map of multi-cell SRF cavities is shown. The temperature mapping result is possible to establish a relationship between the surface resistivity and the magnetic field as well. Unlike the RF method which is average value of the surface resistance, the T-map results give local surface resistivity versus magnetic field. BCS theory assumes the surface resistivity is independent to the magnetic field. The T-map results, however, suggest that the surface resistance at high-loss region is field dependent and caused Q-slope.

THIOA01

Infrastructure, Methods and Test Results for the Testing of 800 Series Cavities for the European XFEL

cavity, coupling, operation, controls

812

D. Reschke
DESY, Hamburg, Germany

Funding: The research leading to these results has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no 283745 (CRISP).
The main linac of the European XFEL will consist of 100 accelerator modules, i.e. 800 superconducting accelerator cavities operated at a design gradient of 23.6 MV/m. The fabrication and surface preparation of the cavities in industry is in full swing. This talk describes the infrastructure and procedures of the vertical acceptance test in the "Accelerator Module Test Facility AMTF" at DESY. The present status of the test results is given.

Slides THIOA01 [1.998 MB]

THIOC04

Demonstration of RF Stabilities in STF 9-cell Cavities Aiming for the Near Quench Limit Operation

operation, cavity, LLRF, controls

865

M. Omet
Sokendai, Ibaraki, Japan
T. Matsumoto, S. Michizono, T. Miura
KEK, Ibaraki, Japan

In preparation of ILC an operation of two superconducting cavities controlled by digital LLRF techniques at different gradients (16 MV/m, 24 MV/m) with flat flattops and a 6.4 mA beam was demonstrated, which is only possible by PkQL control (individual setting of driving power and loaded Q per cavity). The vector sum stabilities were ΔA/A = 0.009%rms and Δφ = 0.009°rms. Since in ILC the cavity gradient spread is large (31.5 MV/m±20%) the required range of loaded Q values is 3·10⁶ to 10⁷. High loaded Q operation with a 6.1 mA beam at 2·10⁷ was demonstrated. The stabilities were ΔA/A = 0.008%rms and Δφ = 0.014°rms. Furthermore a near klystron operation within 5% of saturation was performed with a 6.2 mA beam. The stabilities were ΔA/A = 0.010%rms and Δφ = 0.009°rms.

Slides THIOC04 [1.448 MB]

THP002

Design of 3-Cell Travelling Wave Cavity for High Gradient Test

cavity, accelerating-gradient, pick-up, niobium

892

P.V. Avrakhov, A. Kanareykin, R.A. Kostin, Y. Xie
Euclid TechLabs, LLC, Solon, Ohio, USA
S. Kazakov, N. Solyak, V.P. Yakovlev
Fermilab, Batavia, USA

Utilization of a superconducting traveling wave accelerating (STWA) structure with small phase advance per cell for future high energy linear colliders may provide accelerating gradient 1.2/1.4 times larger [1] than standing wave structure. However, the STWA structure requires a feedback waveguide [1]. Recent tests of 1.3 GHz model of a single-cell cavity with waveguide feedback demonstrated an accelerating gradient comparable to the gradient in a single-cell ILC-type cavity from the same manufacturer [2]. In the present paper a design for a STWA resonator with a 3-cell accelerating cavity for high gradient tests is considered. Methods to create and support the traveling wave in this structure are discussed. The results of detailed studies of the mechanical and tuning properties of the superconducting resonator with 3-cell traveling wave accelerating structure are also presented.

THP079

Improvement of the Pneumatic Frequency Tuner of the Superconducting Resonators at IUAC

controls, linac, cavity, vacuum

1107

A. Pandey, G.K. Chaudhari, R.N. Dutt, S. Ghosh, D. Kanjilal, J. Karmakar, D.S. Mathuria, P. Patra, A. Rai, A. Roy, B.K. Sahu, S.K. Saini
IUAC, New Delhi, India

The existing phase locking scheme of the quarter wave resonators used in superconducting linear accelerator of Inter University Accelerator Centre consists of a fast (electronic) and a slow time scale (pneumatic) control. Presently, helium gas operated mechanical tuners are being used to phase lock the resonators against the master oscillator frequency and different ion beams have been accelerated and delivered to conduct experiments. The present pneumatic frequency tuner has two limitations: (a) no proportional flow control in vacuum condition (b) large hysteresis problem in the proportional valve responsible for gas flow control. Due to these limitations, the system becomes non-linear and the response time is very slow (~sec). Using the existing system, phase locking of a resonator becomes delicate and time consuming. In addition, it was found to be difficult to implement auto phase locking mechanism on the resonator. To overcome these problems and to improve the dynamics of the existing tuner, a new pneumatic tuning system has been adopted. Details of the existing tuning mechanism and the modified tuning system along with the test results will be presented in the paper.

THP081

Development of a Slow Tuner for the 162.5 MHz Superconducting Half-Wave Resonator in IMP

cavity, cryomodule, low-level-rf, controls

1115

S. He, Y. He, Y.L. Huang, L.B. Liu, F.F. Wang, R.X. Wang, X.W. Wang, W.M. Yue, S.H. Zhang, H.W. Zhao
IMP, Lanzhou, People's Republic of China

Funding: This work is supported by Strategic Priority Research Program of CAS (XDA0302)and National Natural Science Foundation of China (91026004)
Within the framework of the C-ADS project, IMP has proposed a 162.5MHz HWR Superconducting cavity for low energy section(β=0.09) of high power proton linear accelerators. A compact slow tuner has been developed for final tuning of the resonance frequency of the cavity after cooling down to operating temperature and to compensate microphonics and Lorentz force detuning. The slow tuner is driven by an external stepper motor and gear box for coarse cavity adjustment. To reduce the force requirements of the actuator, a lever arm and scissor jack mechanism have been applied. The tuner design and recent results of warm tests as the first prototype are presented.

THP085

Equipping FLASH with MTCA.4-based LLRF System

LLRF, controls, cryomodule, cavity

1126

J. Branlard, V. Ayvazyan, L. Butkowski, M.K. Grecki, M. Hoffmann, F. Ludwig, U. Mavrič, S. Pfeiffer, K.P. Przygoda, H. Schlarb, Ch. Schmidt, H.C. Weddig
DESY, Hamburg, Germany
W. Cichalewski, D.R. Makowski, A. Piotrowski
TUL-DMCS, Łódź, Poland
K. Czuba, I. Rutkowski, D. Sikora, L. Zembala, M. Żukociński
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
I.M. Kudla
NCBJ, Świerk/Otwock, Poland
K. Oliwa, W. Wierba
IFJ-PAN, Kraków, Poland

The Free-Electron Laser in Hamburg (FLASH) is now equipped with a MicroTCA-based (MTCA.4) low-level radio frequency (LLRF) system, to replace the previous VME system and to serve as a test bench for the European X-ray Free Electron Laser (XFEL) LLRF system. This paper presents details on the new FLASH LLRF system setup, including installations inside the radiation prone tunnel environment. The benefits and preliminary results of the newly installed system are also given.

THP086

LLRF System Design and Performance for XFEL Cryomodules Continuous Wave Operation

operation, cavity, LLRF, cryomodule

1129

J. Branlard, V. Ayvazyan, L. Butkowski, K.P. Przygoda, H. Schlarb, J.K. Sekutowicz
DESY, Hamburg, Germany
W. Cichalewski, A. Piotrowski
TUL-DMCS, Łódź, Poland
W. Jałmużna
Embedded Integrated Control Systems GmbH, Hamburg, Germany
J. Szewiński
NCBJ, Świerk/Otwock, Poland

The Cryomodule Test Bench (CMTB) at DESY is equipped with a 100 kW Inductive Output Tube (IOT) allowing the test of superconducting cryomodules in continuous wave (CW) operation mode. Although significantly different from the nominal pulsed operation mode of the European X-Ray Free Electron Laser (XFEL), CW operation can be handled by the same Low-level Radio Frequency (LLRF) system, within minor firmware modifications. The hardware details of the LLRF setup at CMTB, the firmware and software architecture and performance results from the last CW test are presented in this contribution.

THP089

Design of LLRF System for RAON

LLRF, controls, FPGA, target

1135

H. Do, O.R. Choi, J. Han, J.-W. Kim
IBS, Daejeon, Republic of Korea
C.K. Hwang
KAERI, Daejon, Republic of Korea

The low-level RF (LLRF) system being designed for RAON will allow research in the rare isotope beam facility. The LLRF system is used to feed the superconducting quarter-wave resonator having the frequency of 81.25 MHz with controlled the amplitude and phase of RF. The LLRF system uses a field programmable gate array (FPGA) to provide controlled RF amplitude and phase with ±1° and less than ±1% of stabilities, respectively. The resolution and working range is 0.004 dB and 20 dB in amplitude, respectively, and 0.5° and 360° in phase. For the RF performance test, a prototype of LLRF system is designed and fabricated. This paper will describe the design detail. Also, testing results of the prototype of LLRF system are presented.