SRF2017 - List of Keywords (LLRF)

Paper	Title	Other Keywords	Page
MOPB040	ESS High-beta Cavity Test Preparations at Daresbury Laboratory	ion, cavity, niobium, SRF	137
	P.A. Smith, L. Bizel-Bizellot, K.D. Dumbell, M. Ellis, P. Goudket, A.J. Moss, E.F. Palade, S.M. Pattalwar, M.D. Pendleton, A.E. Wheelhouse STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Science and Technology Facility Council is responsible for supplying, and testing 84 High beta elliptical SRF cavities, as part of the UK In Kind Contribution to the European Spallation Source (ESS). The High-β=0.86, cavities have been designed by CEA- Saclay and are a five cell Niobium cavity operating at 704.42 MHz. They are required to provide an accelerating gradient of 19.9 MV/m at an unloaded Q of 5x10⁹. Preparations are underway to upgrade the cryogenic and RF facilities at Daresbury laboratory prior to the arrival of the first cavities. As part of these arrangements, a niobium coaxial resonator has been manufactured, to validate the test facility. The design considerations, for the coaxial resonator are presented, along with preliminary results. The RF measurement system to perform the cavity conditioning and testing is also presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB040
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MOPB072	The Development of the LLRF Control System for the New High Power Test Stand of Couplers	ion, vacuum, controls, FPGA	227
	L. Chen, W. Chang, T.C. Jiang, C.L. Li, Y.M. Li, R.X. Wang, S.H. Zhang IMP/CAS, Lanzhou, People's Republic of China
	RF power conditioning is an effective way to suppress multipacting in fundamental mode power couplers. Room temperature test-stand conditioning is an essential step that can be hardly circumvented before couplers are installed on SC cavities. Based on our original one, a new test-stand has been designed and being assembled at IMP. It can work as a multi-task platform conditioning different couplers, including couplers for HWR010 cavities and HWR015 cavities. It is also featured with the capacity to flexibly change β according to different specifications. A variety of conditioning modes have been incorporated into the LLRF system, including frequency sweeping mode, amplitude sweeping mode, arbitrary-duty-cycle mode and triangle-wave mode. In addition, smartly-conditioning has been achieved because of the accomplishment of smart interlocks and automatic reset in the system.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB072
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FRXBA01	LLRF Commissioning at the European XFEL	ion, MMI, FEL, cavity	941
	M. Omet, V. Ayvazyan, J. Branlard, L. Butkowski, M. Fenner, M.K. Grecki, M. Hierholzer, M. Hoffmann, M. Killenberg, D. Kühn, F. Ludwig, U. Mavrič, S. Pfeiffer, H. Pryschelski, K.P. Przygoda, R. Rybaniec, H. Schlarb, Ch. Schmidt, B. Szczepanski, H.C. Weddig DESY, Hamburg, Germany W. Cichalewski, D.R. Makowski, F. Makowski, A. Mielczarek TUL-DMCS, Łódź, Poland K. Czuba, B. Gąsowski, S. Hanasz, P.K. Jatczak, D. Kolcz, T.P. Leśniak, D. Sikora Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland
	The European X-ray Free-Electron Laser (XFEL) at Deutsches Elektronen-Synchrotron (DESY), Hamburg, Germany is a user facility under commissioning, providing ultrashort X-ray flashes with a high brilliance in the near future. All LLRF stations of the injector, covering the normal conducting RF gun, A1 (8 1.3 GHz superconducting cavities (SCs) and AH1 (8 3.9 GHz SCs), were successfully commissioned by the end of 2015. The injector was operated with beam transmission to the injector dump since then. After the conclusion of the construction work in the XFEL accelerator tunnel (XTL), the commissioning of 22 LLRF stations (A2 to A23) started with the beginning of 2017. Every station consists of a semi-distributed LLRF system controlling 32 1.3 GHz SCs. Stable operation with beam transport to the main dump (TLD) was achieved. The commissioning procedure applied, experience gained and performance reached are described.
	Slides FRXBA01 [2.159 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-FRXBA01
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FRXBA02	High Precision RF Control for SRF Cavities in LCLS-II	ion, cavity, controls, feedback	944
	L.R. Doolittle, K.S. Campbell, Q. Du, G. Huang, J.A. Jones, C. Serrano, V.K. Vytla LBNL, Berkeley, California, USA S. Babel, A.L. Benwell, M. Boyes, G.W. Brown, D. Cha, J.H. De Long, J.A. Diaz Cruz, D.B. Greg, B. Hong, R.S. Kelly, A. McCollough, A. Ratti, C.H. Rivetta SLAC, Menlo Park, California, USA R. Bachimanchi, C. Hovater, D.J. Seidman JLab, Newport News, Virginia, USA B.E. Chase, E. Cullerton, J. Einstein, D.W. Klepec Fermilab, Batavia, Illinois, USA
	Funding: This work supported under DOE Contract DE-AC02-76SF00515 The unique properties of SRF cavities enable a new generation of X-ray light sources in XFEL and LCLS-II. The LCLS-II design calls for 280 L-band cavities to be operated in CW mode with a Q_L of 4x10⁷, using Single-Source Single-Cavity control. The target RF field stability is 0.01% and 0.01 degree for the band above 1 Hz. Hardware and software implementing a digital LLRF system has been constructed by a four-lab collaboration to minimize known contributors to cavity RF field fluctuation. Efforts include careful attachment to the phase reference line, and minimizing the effects of RF crosstalk by placing forward and reverse signals in chassis separate from the cavity measurement. A low-noise receiver/digitizer section will allow feedback to operate with high proportional gain without excessive noise being sent to the drive amplifier. Test results will show behavior on prototype cryomodules at FNAL and JLab, ahead of the 2018 final accelerator installation.
	Slides FRXBA02 [3.425 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-FRXBA02
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPB040

ESS High-beta Cavity Test Preparations at Daresbury Laboratory

ion, cavity, niobium, SRF

137

P.A. Smith, L. Bizel-Bizellot, K.D. Dumbell, M. Ellis, P. Goudket, A.J. Moss, E.F. Palade, S.M. Pattalwar, M.D. Pendleton, A.E. Wheelhouse
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Science and Technology Facility Council is responsible for supplying, and testing 84 High beta elliptical SRF cavities, as part of the UK In Kind Contribution to the European Spallation Source (ESS). The High-β=0.86, cavities have been designed by CEA- Saclay and are a five cell Niobium cavity operating at 704.42 MHz. They are required to provide an accelerating gradient of 19.9 MV/m at an unloaded Q of 5x10⁹. Preparations are underway to upgrade the cryogenic and RF facilities at Daresbury laboratory prior to the arrival of the first cavities. As part of these arrangements, a niobium coaxial resonator has been manufactured, to validate the test facility. The design considerations, for the coaxial resonator are presented, along with preliminary results. The RF measurement system to perform the cavity conditioning and testing is also presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB040

Export •

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

MOPB072

The Development of the LLRF Control System for the New High Power Test Stand of Couplers

ion, vacuum, controls, FPGA

227

L. Chen, W. Chang, T.C. Jiang, C.L. Li, Y.M. Li, R.X. Wang, S.H. Zhang
IMP/CAS, Lanzhou, People's Republic of China

RF power conditioning is an effective way to suppress multipacting in fundamental mode power couplers. Room temperature test-stand conditioning is an essential step that can be hardly circumvented before couplers are installed on SC cavities. Based on our original one, a new test-stand has been designed and being assembled at IMP. It can work as a multi-task platform conditioning different couplers, including couplers for HWR010 cavities and HWR015 cavities. It is also featured with the capacity to flexibly change β according to different specifications. A variety of conditioning modes have been incorporated into the LLRF system, including frequency sweeping mode, amplitude sweeping mode, arbitrary-duty-cycle mode and triangle-wave mode. In addition, smartly-conditioning has been achieved because of the accomplishment of smart interlocks and automatic reset in the system.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB072

Export •

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

FRXBA01

LLRF Commissioning at the European XFEL

ion, MMI, FEL, cavity

941

M. Omet, V. Ayvazyan, J. Branlard, L. Butkowski, M. Fenner, M.K. Grecki, M. Hierholzer, M. Hoffmann, M. Killenberg, D. Kühn, F. Ludwig, U. Mavrič, S. Pfeiffer, H. Pryschelski, K.P. Przygoda, R. Rybaniec, H. Schlarb, Ch. Schmidt, B. Szczepanski, H.C. Weddig
DESY, Hamburg, Germany
W. Cichalewski, D.R. Makowski, F. Makowski, A. Mielczarek
TUL-DMCS, Łódź, Poland
K. Czuba, B. Gąsowski, S. Hanasz, P.K. Jatczak, D. Kolcz, T.P. Leśniak, D. Sikora
Warsaw University of Technology, Institute of Electronic Systems, Warsaw, Poland

The European X-ray Free-Electron Laser (XFEL) at Deutsches Elektronen-Synchrotron (DESY), Hamburg, Germany is a user facility under commissioning, providing ultrashort X-ray flashes with a high brilliance in the near future. All LLRF stations of the injector, covering the normal conducting RF gun, A1 (8 1.3 GHz superconducting cavities (SCs) and AH1 (8 3.9 GHz SCs), were successfully commissioned by the end of 2015. The injector was operated with beam transmission to the injector dump since then. After the conclusion of the construction work in the XFEL accelerator tunnel (XTL), the commissioning of 22 LLRF stations (A2 to A23) started with the beginning of 2017. Every station consists of a semi-distributed LLRF system controlling 32 1.3 GHz SCs. Stable operation with beam transport to the main dump (TLD) was achieved. The commissioning procedure applied, experience gained and performance reached are described.

Slides FRXBA01 [2.159 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-FRXBA01

Export •

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

FRXBA02

High Precision RF Control for SRF Cavities in LCLS-II

ion, cavity, controls, feedback

944

L.R. Doolittle, K.S. Campbell, Q. Du, G. Huang, J.A. Jones, C. Serrano, V.K. Vytla
LBNL, Berkeley, California, USA
S. Babel, A.L. Benwell, M. Boyes, G.W. Brown, D. Cha, J.H. De Long, J.A. Diaz Cruz, D.B. Greg, B. Hong, R.S. Kelly, A. McCollough, A. Ratti, C.H. Rivetta
SLAC, Menlo Park, California, USA
R. Bachimanchi, C. Hovater, D.J. Seidman
JLab, Newport News, Virginia, USA
B.E. Chase, E. Cullerton, J. Einstein, D.W. Klepec
Fermilab, Batavia, Illinois, USA

Funding: This work supported under DOE Contract DE-AC02-76SF00515
The unique properties of SRF cavities enable a new generation of X-ray light sources in XFEL and LCLS-II. The LCLS-II design calls for 280 L-band cavities to be operated in CW mode with a Q_L of 4x10⁷, using Single-Source Single-Cavity control. The target RF field stability is 0.01% and 0.01 degree for the band above 1 Hz. Hardware and software implementing a digital LLRF system has been constructed by a four-lab collaboration to minimize known contributors to cavity RF field fluctuation. Efforts include careful attachment to the phase reference line, and minimizing the effects of RF crosstalk by placing forward and reverse signals in chassis separate from the cavity measurement. A low-noise receiver/digitizer section will allow feedback to operate with high proportional gain without excessive noise being sent to the drive amplifier. Test results will show behavior on prototype cryomodules at FNAL and JLab, ahead of the 2018 final accelerator installation.

Slides FRXBA02 [3.425 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-FRXBA02

Export •

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