SRF2017 - List of Keywords (MMI)

Paper	Title	Other Keywords	Page
MOXA02	The Commissioning of the European XFEL Linac and its Performance	ion, FEL, linac, cavity	1
	D. Reschke, W. Decking, N. Walker, H. Weise DESY, Hamburg, Germany
	Funding: Presented on behalf of the XFEL Accelerator Consortium. Work supported by the respective funding agencies of the contributing institutes; for details see www.xfel.eu. The main linac of the superconducting accelerator of the European XFEL presently consists of 96 accelerator modules, each housing eight 1.3 GHz TESLA-type cavi-ties, with an average design gradient of 23.6 MV/m. The performance of each individual module has been tested after module assembly in the Accelerator Module Test Facility (AMTF) at DESY. The 2-year period of module installation to the accelerator tunnel was finished in August 2016. In order to recheck and re-establish the performance of the input power couplers, warm processing of nearly all installed modules was performed before the first cool-down during Dec 2016 / Jan 2017. Four consecutive modules are connected to one 10 MW klystron and form a so-called RF station, which is powered and controlled individually during operation. By June 2017 23 of 25 RF stations have been commissioned for beam acceleration including frequency tuning, various calibrations and LLRF adjustments. A preliminary beam energy of 14 GeV was achieved, which is sufficient for first lasing experiments. No significant performance degradation has been observed so far. The commissioning experience and the available RF performance data will be presented.
	Slides MOXA02 [6.896 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOXA02
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MOPB003	A New High Resolution Optical System for Inspection of Gun-and Multi-cell Resonators in ISO-4 Cleanrooms	ion, cavity, gun, SRF	47
	M. Schalwat, R. Bandelmann, A. Daniel, N. Krupka, A. Matheisen, S.T. Sievers DESY, Hamburg, Germany
	Optical inspection of the inner surface of superconducting resonators was established during European XFEL cavity production by usage of the so called OBACHT optical inspection. In addition to the surface inspection by OBACHT a new optical inspection system with integrated high resolution camera is set up at DESY. It allows inspection of multi-cell resonators as well as gun cavity resonators with only single side accessibility to the inner surface. A prototype was commissioned and optical inspections were done with OBACHT and the new system in parallel. Two SRF gun cavities were inspected by this optical system and origin of limitations of the resonators were identified.
	Poster MOPB003 [0.220 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB003
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MOPB077	Operational Experience of the European-XFEL 3.9 GHz Coaxial Tuners	ion, cavity, FEL, operation	240
	R. Paparella, A. Bellandi, A. Bignami, A. Bosotti, D. Sertore INFN/LASA, Segrate (MI), Italy C.G. Maiano ESS, Lund, Sweden P. Pierini DESY, Hamburg, Germany
	The European-XFEL injector hosts a third-harmonic section composed by a module with eigth 3.9 GHz cavities equipped with a coaxial frequency tuner inspired by INFN-LASA Blade Tuner design. The 3.9 GHz tuning system met specifications during all the injector runs in 2016 up to the recent commissioning of the entire linac; it matched the required tuning range and frequency sensitivity although higher than expected cavity detuning was experienced during pressure transients in the cryogenic system. An analysis of all collected experimental data is reported in this paper together with the strategy developed to provide a sound and effective retuning routine to the control room operator.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB077
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MOPB111	European XFEL Linac RF System Conditioning and Operating Test	ion, cavity, FEL, vacuum	328
	D. Kostin, J. Branlard, A. Gössel, O. Hensler, M. Omet, D. Reschke, A.A. Sulimov, N. Walker, M. Wiencek DESY, Hamburg, Germany
	96 accelerating modules with 768 TESLA/European-XFEL type superconducting cavities were installed in the European XFEL LINAC tunnel (XTL) in the fall 2016. Warm conditioning of the RF system - High/Low Level RF System and main input couplers - begun even before finishing the accelerator installation works. All modules were conditioned and tested prior to the installation in the tunnel in the AMTF test stand at DESY. Nevertheless, due to some repair activities on warm input coupler parts, warm conditioning was needed on a few modules/couplers. Cooling down to 2K begun in December 2016 and was finished in January 2017. Since then cold conditioning and tests are running. Several cavities in a few modules did show the multipacting (MP) effects, mostly because a cavity vacuum was filled with a dry nitrogen for before mentioned repairs on couplers in some modules. Said MP effects were seen in AMTF as well. All MP effects were successfully conditioned until now. The warm/cold RF system conditioning and its results/experiences/limits are described and discussed.
	Poster MOPB111 [1.267 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB111
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TUPB013	Advanced Manufacturing Techniques for the Fabrication of Hl-LHC Crab Cavities at CERN	ion, cavity, niobium, simulation	409
	M. Garlaschè CERN, Geneva, Switzerland
	RF Crab Cavities are an essential part of the HL-LHC upgrade at CERN. Two concepts of such systems are being developed: the Double Quarter Wave (DQW) and the RF Dipole (RFD). The following paper describes the advanced manufacturing techniques developed for the fabrication of the DQW cavity prototype with an outlook on the upcoming RFD prototype production.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB013
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TUPB074	RF Performance of Multi-cell Scale Niobium SRF Cavities Prepared with HF Free Bipolar Electro-polishing at Faraday Technology	cavity, ion, SRF, niobium	567
	F. Furuta, M. Ge, T. Gruber, J.J. Kaufman, M. Liepe, J. Sears Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA T.D. Hall, M.E. Inman, R. Radhakrishnan, S.T. Snyder, E.J. Taylor Faraday Technology, Inc., Clayton, Ohio, USA
	Cornell's SRF group and Faraday Technology, Inc. have been collaborating on two phase-II SBIR projects. One of them is the development and commissioning of a 9-cell scale HF free Bipolar Electro-Polishing (BEP) system. Faraday Technology had completed the proof of principle on BEP with single cell scale prior to the work reported here, and has now developed a new 9-cell scale BEP system. Cornell has fabricated three single cell cavities and has assembled them together as a 9-cell scale test string. The 9-cell scale test string has received BEP at Faraday Technology and RF testing has been performed on the three single cell cavities one-by-one at Cornell. Here we give a status update on the new 9-cell scale BEP system commissioning and on results from RF tests of the BEP cavities.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB074
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FRXBA01	LLRF Commissioning at the European XFEL	ion, LLRF, 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)

Paper

Title

Other Keywords

Page

MOXA02

The Commissioning of the European XFEL Linac and its Performance

ion, FEL, linac, cavity

1

D. Reschke, W. Decking, N. Walker, H. Weise
DESY, Hamburg, Germany

Funding: Presented on behalf of the XFEL Accelerator Consortium. Work supported by the respective funding agencies of the contributing institutes; for details see www.xfel.eu.
The main linac of the superconducting accelerator of the European XFEL presently consists of 96 accelerator modules, each housing eight 1.3 GHz TESLA-type cavi-ties, with an average design gradient of 23.6 MV/m. The performance of each individual module has been tested after module assembly in the Accelerator Module Test Facility (AMTF) at DESY. The 2-year period of module installation to the accelerator tunnel was finished in August 2016. In order to recheck and re-establish the performance of the input power couplers, warm processing of nearly all installed modules was performed before the first cool-down during Dec 2016 / Jan 2017. Four consecutive modules are connected to one 10 MW klystron and form a so-called RF station, which is powered and controlled individually during operation. By June 2017 23 of 25 RF stations have been commissioned for beam acceleration including frequency tuning, various calibrations and LLRF adjustments. A preliminary beam energy of 14 GeV was achieved, which is sufficient for first lasing experiments. No significant performance degradation has been observed so far. The commissioning experience and the available RF performance data will be presented.

Slides MOXA02 [6.896 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOXA02

Export •

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

MOPB003

A New High Resolution Optical System for Inspection of Gun-and Multi-cell Resonators in ISO-4 Cleanrooms

ion, cavity, gun, SRF

47

M. Schalwat, R. Bandelmann, A. Daniel, N. Krupka, A. Matheisen, S.T. Sievers
DESY, Hamburg, Germany

Optical inspection of the inner surface of superconducting resonators was established during European XFEL cavity production by usage of the so called OBACHT optical inspection. In addition to the surface inspection by OBACHT a new optical inspection system with integrated high resolution camera is set up at DESY. It allows inspection of multi-cell resonators as well as gun cavity resonators with only single side accessibility to the inner surface. A prototype was commissioned and optical inspections were done with OBACHT and the new system in parallel. Two SRF gun cavities were inspected by this optical system and origin of limitations of the resonators were identified.

Poster MOPB003 [0.220 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB003

Export •

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

MOPB077

Operational Experience of the European-XFEL 3.9 GHz Coaxial Tuners

ion, cavity, FEL, operation

240

R. Paparella, A. Bellandi, A. Bignami, A. Bosotti, D. Sertore
INFN/LASA, Segrate (MI), Italy
C.G. Maiano
ESS, Lund, Sweden
P. Pierini
DESY, Hamburg, Germany

The European-XFEL injector hosts a third-harmonic section composed by a module with eigth 3.9 GHz cavities equipped with a coaxial frequency tuner inspired by INFN-LASA Blade Tuner design. The 3.9 GHz tuning system met specifications during all the injector runs in 2016 up to the recent commissioning of the entire linac; it matched the required tuning range and frequency sensitivity although higher than expected cavity detuning was experienced during pressure transients in the cryogenic system. An analysis of all collected experimental data is reported in this paper together with the strategy developed to provide a sound and effective retuning routine to the control room operator.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB077

Export •

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

MOPB111

European XFEL Linac RF System Conditioning and Operating Test

ion, cavity, FEL, vacuum

328

D. Kostin, J. Branlard, A. Gössel, O. Hensler, M. Omet, D. Reschke, A.A. Sulimov, N. Walker, M. Wiencek
DESY, Hamburg, Germany

96 accelerating modules with 768 TESLA/European-XFEL type superconducting cavities were installed in the European XFEL LINAC tunnel (XTL) in the fall 2016. Warm conditioning of the RF system - High/Low Level RF System and main input couplers - begun even before finishing the accelerator installation works. All modules were conditioned and tested prior to the installation in the tunnel in the AMTF test stand at DESY. Nevertheless, due to some repair activities on warm input coupler parts, warm conditioning was needed on a few modules/couplers. Cooling down to 2K begun in December 2016 and was finished in January 2017. Since then cold conditioning and tests are running. Several cavities in a few modules did show the multipacting (MP) effects, mostly because a cavity vacuum was filled with a dry nitrogen for before mentioned repairs on couplers in some modules. Said MP effects were seen in AMTF as well. All MP effects were successfully conditioned until now. The warm/cold RF system conditioning and its results/experiences/limits are described and discussed.

Poster MOPB111 [1.267 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB111

Export •

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

TUPB013

Advanced Manufacturing Techniques for the Fabrication of Hl-LHC Crab Cavities at CERN

ion, cavity, niobium, simulation

409

M. Garlaschè
CERN, Geneva, Switzerland

RF Crab Cavities are an essential part of the HL-LHC upgrade at CERN. Two concepts of such systems are being developed: the Double Quarter Wave (DQW) and the RF Dipole (RFD). The following paper describes the advanced manufacturing techniques developed for the fabrication of the DQW cavity prototype with an outlook on the upcoming RFD prototype production.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB013

Export •

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

TUPB074

RF Performance of Multi-cell Scale Niobium SRF Cavities Prepared with HF Free Bipolar Electro-polishing at Faraday Technology

cavity, ion, SRF, niobium

567

F. Furuta, M. Ge, T. Gruber, J.J. Kaufman, M. Liepe, J. Sears
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
T.D. Hall, M.E. Inman, R. Radhakrishnan, S.T. Snyder, E.J. Taylor
Faraday Technology, Inc., Clayton, Ohio, USA

Cornell's SRF group and Faraday Technology, Inc. have been collaborating on two phase-II SBIR projects. One of them is the development and commissioning of a 9-cell scale HF free Bipolar Electro-Polishing (BEP) system. Faraday Technology had completed the proof of principle on BEP with single cell scale prior to the work reported here, and has now developed a new 9-cell scale BEP system. Cornell has fabricated three single cell cavities and has assembled them together as a 9-cell scale test string. The 9-cell scale test string has received BEP at Faraday Technology and RF testing has been performed on the three single cell cavities one-by-one at Cornell. Here we give a status update on the new 9-cell scale BEP system commissioning and on results from RF tests of the BEP cavities.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB074

Export •

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

FRXBA01

LLRF Commissioning at the European XFEL

ion, LLRF, 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)