SRF2017 - List of Authors (Reschke, D.)

Paper	Title	Page
MOXA02	The Commissioning of the European XFEL Linac and its Performance	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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MOPB013	European XFEL Input Coupler Experiences and Challenges in a Test Field	78
	F. Hoffmann, D. Kostin, W.-D. Möller, D. Reschke, M. Wiencek DESY, Hamburg, Germany
	102 European XFEL accelerating modules with 816 superconducting cavities and main input RF power couplers were assembled and then tested at DESY prior to installation in the European XFEL tunnel. In the Accelerating Module Test Facility (AMTF) warm and cold RF tests were done. The test results went directly to the operational setup for the LINAC. Main input couplers did present several problems during the tests, resulting in some minor coupler design changes as well as in a few repair actions. The experience got from the said testing operation is worth to be shared and is presented here together with a discussion.
	Poster MOPB013 [0.648 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB013
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MOPB106	Test Results of the European XFEL Serial-production Accelerator Modules	312
	K. Kasprzak, M. Wiencek, A. Zwozniak IFJ-PAN, Kraków, Poland D. Kostin, D. Reschke, N. Walker DESY, Hamburg, Germany
	The serial-production tests of 100 cryomodules for the European XFEL have been finished. In this paper the statistics of the cold RF measurements in the AMTF (Accelerator Module Test Facility) are reported for all the modules. In addition comparison between the cavity vertical test results and module test results are presented.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB106
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MOPB111	European XFEL Linac RF System Conditioning and Operating Test	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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THPB007	Nitrogen Infusion R&D on Single Cell Cavities at DESY	759
	M. Wenskat, D. Reschke, J. Schaffran DESY, Hamburg, Germany A.L. Prudnikava University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany
	A first series of single cell cavities underwent the "Nitrogen Infusion" treatment at DESY. Samples, which were in the furnace together with the cavities, underwent a series of SEM/EDX measurements and showed some unexpected structures. In parallel, the cavity performance deteriorated after the treatment. The furnace pressure and temperature and the residual gases during the treatment were analyzed and the possible cause for the deterioration has been found. Steps to prevent this deterioration in following treatments are discussed and first results are shown.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-THPB007
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

The Commissioning of the European XFEL Linac and its Performance

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)

MOPB013

European XFEL Input Coupler Experiences and Challenges in a Test Field

78

F. Hoffmann, D. Kostin, W.-D. Möller, D. Reschke, M. Wiencek
DESY, Hamburg, Germany

102 European XFEL accelerating modules with 816 superconducting cavities and main input RF power couplers were assembled and then tested at DESY prior to installation in the European XFEL tunnel. In the Accelerating Module Test Facility (AMTF) warm and cold RF tests were done. The test results went directly to the operational setup for the LINAC. Main input couplers did present several problems during the tests, resulting in some minor coupler design changes as well as in a few repair actions. The experience got from the said testing operation is worth to be shared and is presented here together with a discussion.

Poster MOPB013 [0.648 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB013

Export •

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

MOPB106

Test Results of the European XFEL Serial-production Accelerator Modules

312

K. Kasprzak, M. Wiencek, A. Zwozniak
IFJ-PAN, Kraków, Poland
D. Kostin, D. Reschke, N. Walker
DESY, Hamburg, Germany

The serial-production tests of 100 cryomodules for the European XFEL have been finished. In this paper the statistics of the cold RF measurements in the AMTF (Accelerator Module Test Facility) are reported for all the modules. In addition comparison between the cavity vertical test results and module test results are presented.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB106

Export •

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

MOPB111

European XFEL Linac RF System Conditioning and Operating Test

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)

THPB007

Nitrogen Infusion R&D on Single Cell Cavities at DESY

759

M. Wenskat, D. Reschke, J. Schaffran
DESY, Hamburg, Germany
A.L. Prudnikava
University of Hamburg, Institut für Experimentalphysik, Hamburg, Germany

A first series of single cell cavities underwent the "Nitrogen Infusion" treatment at DESY. Samples, which were in the furnace together with the cavities, underwent a series of SEM/EDX measurements and showed some unexpected structures. In parallel, the cavity performance deteriorated after the treatment. The furnace pressure and temperature and the residual gases during the treatment were analyzed and the possible cause for the deterioration has been found. Steps to prevent this deterioration in following treatments are discussed and first results are shown.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-THPB007

Export •

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