SRF2015 - List of Keywords (quadrupole)

Paper	Title	Other Keywords	Page
MOPB067	Steps Towards Superconducting CW-LINAC for Heavy Ions at GSI	linac, ion, heavy-ion, cavity	262
	M. Miski-Oglu, M. Amberg, K. Aulenbacher, V. Gettmann HIM, Mainz, Germany W.A. Barth, M. Heilmann, S. Mickat, S. Yaramyshev GSI, Darmstadt, Germany M. Basten, D. Bänsch, F.D. Dziuba, H. Podlech, U. Ratzinger IAP, Frankfurt am Main, Germany
	Providing heavy ion beams for the ambitious experiment program at GSI, the Universal Linear Accelerator (UNILAC) serves as a powerful high duty factor (25%) accelerator. Beam time availability for SHE-research will be decreased due to the limitation of the UNILAC providing a proper beam for FAIR simultaneously. To keep the GSI-SHE program competitive on a high level, a standalone sc cw-LINAC in combination with the upgraded GSI High Charge State injector is planned to build. In preparation for this the first linac section (financed by HIM and partly by HGF-ARD-initiative) will be tested in 2015 as a demonstrator. After successful testing the construction of an extended cryomodule comprising two further, but shorter CH cavities is foreseen to test until end of 2017. In this contribution the measurement of the beam parameters at the entrance of CW-Demonstartor, the preliminary simulation of beam dynamics for the first stage of advanced demonstrator will be presented. As a final R&D step towards an entire linac an advanced cryo module comprising up to five CH cavities is envisaged for 2019 serving for first user experiments at the coulomb barrier.
	Poster MOPB067 [2.807 MB]
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TUPB051	Development of Nb3Sn Coatings by Magnetron Sputtering for SRF Cavities	vacuum, radio-frequency, SRF, target	691
	G.J. Rosaz, S. Calatroni, F.M. Leaux, F. Motschmann, Z. Mydlarz, M. Taborelli, W. Vollenberg CERN, Geneva, Switzerland
	Funding: The work is part of EuCARD-2, partly funded by the European Commission, GA 312453 Cost and energy savings are an integral requirement in the design of future particle accelerators. Very low losses SRF accelerating systems, together with high-efficiency cryogenics systems, have the potential of low running costs. The association to the capital cost reduction allowed by thin films coated copper cavities may represent the best overall cost-performance compromise. This strategy has been applied for instance in LEP, the LHC and HIE-ISOLDE with the niobium thin films technology. New materials must be considered to improve the quality factor of the cavities, such as Nb3Sn, which could also ideally operate at higher temperature thus allowing further energy savings. The study considers the possibility to coat a copper resonator with an Nb3Sn layer by means of magnetron sputtering using an alloyed target. We present the impact of the process parameters on the as-deposited layer stoichiometry. The latter is in good agreement with previous results reported in the literature and can be tuned by acting on the coating pressure. The effect of post-coating annealing temperature on the morphology, crystallinity and superconducting properties of the film was also investigated.
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TUPB067	Design and First Measurements of an Alternative Calorimetry Chamber for the HZB Quadrupole Resonator	niobium, SRF, simulation, operation	739
	S. Keckert, R. Kleindienst, J. Knobloch, O. Kugeler HZB, Berlin, Germany
	Funding: The work is part of EuCARD-2, partly funded by the European Commission, GA 312453. The systematic research on superconducting thin films requires dedicated testing equipment. The Quadrupole Resonator (QPR) is a specialized tool to characterize the superconducting properties of circular samples. A calorimetric measurement of the RF surface losses allows the surface resistance to be measured with sub nano-ohm resolution. This measurement can be performed over a wide temperature and magnetic field range, at frequencies of 433, 866 and 1300 MHz. The system at Helmholtz-Zentrum Berlin (HZB) is based on a resonator built at CERN and has been optimized to lower peak electric fields and an improved resolution. An alternative calorimetry chamber has been designed in order to provide flat samples for coating and to ease changing of samples. Furthermore it enables exchangeability of samples between the QPRs at HZB and CERN. With this poster the design and first measurements of the new calorimetry chamber is presented.
	Poster TUPB067 [1.776 MB]
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TUPB104	Series Production of BQU at DESY for the EU-XFEL Module Assembly at CEA Saclay	vacuum, acceleration, cavity, diagnostics	865
	B. van der Horst, M. Helmig, A. Matheisen, S. Saegebarth, M. Schalwat DESY, Hamburg, Germany
	Each of the 10³ XFEL modules foreseen for the EU-XFEL as well as the 3,9 GHZ injector module is equipped with a combination of beam position monitors, superconducting quadrupole and a gate valve connected to the beam position monitor. The subunits are prequalified by the different work package of the EU-XFEL collaboration and handover to the DESY cleanroom. These subunits are assembled in the DESY ISO 4 cleanroom to unit named BQU, quality controlled in respect of cleanliness and handover in status “ready for assembly in ISO 4 cleanroom” for string assembly to the ISO 4 cleanroom located at CEA France. Series production started with production sequences of one unit per week and needed to be accelerated up to five or six units per month (>=1.25 units per week) in beginning of 2015. Analysis of data taken during production and the optimization of work flow for higher production rates are presented.
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TUPB105	String Assembly for the EU-XFEL 3.9 GHz Module at DESY	cavity, alignment, vacuum, linac	869
	M. Schmökel, R. Bandelmann, A. Daniel, A. Matheisen, P. Schilling, B. van der Horst DESY, Hamburg, Germany R. Paparella, P. Pierini, D. Sertore INFN/LASA, Segrate (MI), Italy
	For the injector of the EU- XFEL one so-called 3.9 GHz module is required. This special module houses eight 3.9 GHz s.c. cavities, a beam position monitor and a quadrupole package. The cavities were fabricated and vertically tested as an in-kind contribution to the EU-XFEL by INFN Milano collaborators. The power couplers have been fabricated and conditioned by FNAL. The string assembly took place inside the ISO 4 cleanroom at DESY. A seven meter long alignment and assembly girder for this special string assembly has been designed and fabricated at DESY. The girder facilitates the assembly of the 3.9 GHz resonators with alternating power coupler orientation in ISO 4 cleanrooms. For redundancy and fast action on problems during string assembly, the DESY high pressure rinsing system (HPR) has been modified on the basis of the INFN Milano design for this 3.9 GHz application. The HPR has been qualified by four 3.9 GHz resonators, tested at INFN Milano. The integration of the cavities into Helium vessels, power coupler coupling factor and the power coupler assembly at DESY is qualified by one cavity that has been equipped with Helium tank and a power coupler and tested horizontally.
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WEA1A04	Commissioning Results of the HZB Quadrupole Resonator	niobium, cavity, electron, SRF	930
	R. Kleindienst, A. Burrill, S. Keckert, J. Knobloch, O. Kugeler HZB, Berlin, Germany
	Funding: The research leading to these results has received funding from the European Commission under the FP7 Research Infrastructures project EuCARD-2, grant agreement no.312453 Recent cavity results with niobium have demonstrated the necessity of a good understanding of both the BCS and residual resistance. For a complete picture, and comparison with theory, it is essential that one can measure the RF properties as a function of applied magnetic field, temperature, frequency and ambient magnetic field. Standard cavity measurements are limited in their ability to change all parameters freely and in a controlled manner. On the other hand, most sample measurement setups operate at fairly high frequency, where the surface resistance is always BCS dominated. The quadrupole resonator, originally developed at CERN, is ideally suited for RF characterization of samples at frequencies of 400 and 1300 MHz, between which many of today’s SRF cavities operate. We report on a modified version of the QPR with improved RF figures of merit for high-field operation. Experimental challenges in the commissioning run and alternate designs towards a simpler sample change are shown alongside measurement results of a large grain niobium sample.
	Slides WEA1A04 [5.611 MB]
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THPB004	HOM Calculations for Different Cavities and Beam Induced HOM Power Analysis of ESS	HOM, cavity, sextupole, dipole	1061
	H.J. Zheng, J. Gao IHEP, Beijing, People's Republic of China J.F. Chen INFN/LASA, Segrate (MI), Italy C. Pagani Università degli Studi di Milano & INFN, Segrate, Italy
	For different design of ESS superconducting cavities, the higher order modes (HOM's) of monopoles, dipoles, quadrupoles and sextupoles are found. Their R/Q values are also calculated. Main HOM related issues are the beam instabilities and the HOM induced power especially from TM monopoles. The analysis for the beam induced HOM voltage and power in this paper showed that, if the HOM frequency is a few kHz away from the beam spectrum, it is not a problem. In order to understand the effects of the beam structure, analytic expressions are developed. With these expressions, the induced HOM voltage and power were calculated by assuming external Q for each HOM. Our analysis confirm that, with thebeam structure of ESS and a good cavity design, no special tight tolerances are required for cavity fabrication and no HOM couplers in the cavity beam pipes are planned.
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Paper

Title

Other Keywords

Page

MOPB067

Steps Towards Superconducting CW-LINAC for Heavy Ions at GSI

linac, ion, heavy-ion, cavity

262

M. Miski-Oglu, M. Amberg, K. Aulenbacher, V. Gettmann
HIM, Mainz, Germany
W.A. Barth, M. Heilmann, S. Mickat, S. Yaramyshev
GSI, Darmstadt, Germany
M. Basten, D. Bänsch, F.D. Dziuba, H. Podlech, U. Ratzinger
IAP, Frankfurt am Main, Germany

Providing heavy ion beams for the ambitious experiment program at GSI, the Universal Linear Accelerator (UNILAC) serves as a powerful high duty factor (25%) accelerator. Beam time availability for SHE-research will be decreased due to the limitation of the UNILAC providing a proper beam for FAIR simultaneously. To keep the GSI-SHE program competitive on a high level, a standalone sc cw-LINAC in combination with the upgraded GSI High Charge State injector is planned to build. In preparation for this the first linac section (financed by HIM and partly by HGF-ARD-initiative) will be tested in 2015 as a demonstrator. After successful testing the construction of an extended cryomodule comprising two further, but shorter CH cavities is foreseen to test until end of 2017. In this contribution the measurement of the beam parameters at the entrance of CW-Demonstartor, the preliminary simulation of beam dynamics for the first stage of advanced demonstrator will be presented. As a final R&D step towards an entire linac an advanced cryo module comprising up to five CH cavities is envisaged for 2019 serving for first user experiments at the coulomb barrier.

Poster MOPB067 [2.807 MB]

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reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)

TUPB051

Development of Nb3Sn Coatings by Magnetron Sputtering for SRF Cavities

vacuum, radio-frequency, SRF, target

691

G.J. Rosaz, S. Calatroni, F.M. Leaux, F. Motschmann, Z. Mydlarz, M. Taborelli, W. Vollenberg
CERN, Geneva, Switzerland

Funding: The work is part of EuCARD-2, partly funded by the European Commission, GA 312453
Cost and energy savings are an integral requirement in the design of future particle accelerators. Very low losses SRF accelerating systems, together with high-efficiency cryogenics systems, have the potential of low running costs. The association to the capital cost reduction allowed by thin films coated copper cavities may represent the best overall cost-performance compromise. This strategy has been applied for instance in LEP, the LHC and HIE-ISOLDE with the niobium thin films technology. New materials must be considered to improve the quality factor of the cavities, such as Nb3Sn, which could also ideally operate at higher temperature thus allowing further energy savings. The study considers the possibility to coat a copper resonator with an Nb3Sn layer by means of magnetron sputtering using an alloyed target. We present the impact of the process parameters on the as-deposited layer stoichiometry. The latter is in good agreement with previous results reported in the literature and can be tuned by acting on the coating pressure. The effect of post-coating annealing temperature on the morphology, crystallinity and superconducting properties of the film was also investigated.

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reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)

TUPB067

Design and First Measurements of an Alternative Calorimetry Chamber for the HZB Quadrupole Resonator

niobium, SRF, simulation, operation

739

S. Keckert, R. Kleindienst, J. Knobloch, O. Kugeler
HZB, Berlin, Germany

Funding: The work is part of EuCARD-2, partly funded by the European Commission, GA 312453.
The systematic research on superconducting thin films requires dedicated testing equipment. The Quadrupole Resonator (QPR) is a specialized tool to characterize the superconducting properties of circular samples. A calorimetric measurement of the RF surface losses allows the surface resistance to be measured with sub nano-ohm resolution. This measurement can be performed over a wide temperature and magnetic field range, at frequencies of 433, 866 and 1300 MHz. The system at Helmholtz-Zentrum Berlin (HZB) is based on a resonator built at CERN and has been optimized to lower peak electric fields and an improved resolution. An alternative calorimetry chamber has been designed in order to provide flat samples for coating and to ease changing of samples. Furthermore it enables exchangeability of samples between the QPRs at HZB and CERN. With this poster the design and first measurements of the new calorimetry chamber is presented.

Poster TUPB067 [1.776 MB]

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TUPB104

Series Production of BQU at DESY for the EU-XFEL Module Assembly at CEA Saclay

vacuum, acceleration, cavity, diagnostics

865

B. van der Horst, M. Helmig, A. Matheisen, S. Saegebarth, M. Schalwat
DESY, Hamburg, Germany

Each of the 10³ XFEL modules foreseen for the EU-XFEL as well as the 3,9 GHZ injector module is equipped with a combination of beam position monitors, superconducting quadrupole and a gate valve connected to the beam position monitor. The subunits are prequalified by the different work package of the EU-XFEL collaboration and handover to the DESY cleanroom. These subunits are assembled in the DESY ISO 4 cleanroom to unit named BQU, quality controlled in respect of cleanliness and handover in status “ready for assembly in ISO 4 cleanroom” for string assembly to the ISO 4 cleanroom located at CEA France. Series production started with production sequences of one unit per week and needed to be accelerated up to five or six units per month (>=1.25 units per week) in beginning of 2015. Analysis of data taken during production and the optimization of work flow for higher production rates are presented.

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reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)

TUPB105

String Assembly for the EU-XFEL 3.9 GHz Module at DESY

cavity, alignment, vacuum, linac

869

M. Schmökel, R. Bandelmann, A. Daniel, A. Matheisen, P. Schilling, B. van der Horst
DESY, Hamburg, Germany
R. Paparella, P. Pierini, D. Sertore
INFN/LASA, Segrate (MI), Italy

For the injector of the EU- XFEL one so-called 3.9 GHz module is required. This special module houses eight 3.9 GHz s.c. cavities, a beam position monitor and a quadrupole package. The cavities were fabricated and vertically tested as an in-kind contribution to the EU-XFEL by INFN Milano collaborators. The power couplers have been fabricated and conditioned by FNAL. The string assembly took place inside the ISO 4 cleanroom at DESY. A seven meter long alignment and assembly girder for this special string assembly has been designed and fabricated at DESY. The girder facilitates the assembly of the 3.9 GHz resonators with alternating power coupler orientation in ISO 4 cleanrooms. For redundancy and fast action on problems during string assembly, the DESY high pressure rinsing system (HPR) has been modified on the basis of the INFN Milano design for this 3.9 GHz application. The HPR has been qualified by four 3.9 GHz resonators, tested at INFN Milano. The integration of the cavities into Helium vessels, power coupler coupling factor and the power coupler assembly at DESY is qualified by one cavity that has been equipped with Helium tank and a power coupler and tested horizontally.

Export •

reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)

WEA1A04

Commissioning Results of the HZB Quadrupole Resonator

niobium, cavity, electron, SRF

930

R. Kleindienst, A. Burrill, S. Keckert, J. Knobloch, O. Kugeler
HZB, Berlin, Germany

Funding: The research leading to these results has received funding from the European Commission under the FP7 Research Infrastructures project EuCARD-2, grant agreement no.312453
Recent cavity results with niobium have demonstrated the necessity of a good understanding of both the BCS and residual resistance. For a complete picture, and comparison with theory, it is essential that one can measure the RF properties as a function of applied magnetic field, temperature, frequency and ambient magnetic field. Standard cavity measurements are limited in their ability to change all parameters freely and in a controlled manner. On the other hand, most sample measurement setups operate at fairly high frequency, where the surface resistance is always BCS dominated. The quadrupole resonator, originally developed at CERN, is ideally suited for RF characterization of samples at frequencies of 400 and 1300 MHz, between which many of today’s SRF cavities operate. We report on a modified version of the QPR with improved RF figures of merit for high-field operation. Experimental challenges in the commissioning run and alternate designs towards a simpler sample change are shown alongside measurement results of a large grain niobium sample.

Slides WEA1A04 [5.611 MB]

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reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)

THPB004

HOM Calculations for Different Cavities and Beam Induced HOM Power Analysis of ESS

HOM, cavity, sextupole, dipole

1061

H.J. Zheng, J. Gao
IHEP, Beijing, People's Republic of China
J.F. Chen
INFN/LASA, Segrate (MI), Italy
C. Pagani
Università degli Studi di Milano & INFN, Segrate, Italy

For different design of ESS superconducting cavities, the higher order modes (HOM's) of monopoles, dipoles, quadrupoles and sextupoles are found. Their R/Q values are also calculated. Main HOM related issues are the beam instabilities and the HOM induced power especially from TM monopoles. The analysis for the beam induced HOM voltage and power in this paper showed that, if the HOM frequency is a few kHz away from the beam spectrum, it is not a problem. In order to understand the effects of the beam structure, analytic expressions are developed. With these expressions, the induced HOM voltage and power were calculated by assuming external Q for each HOM. Our analysis confirm that, with thebeam structure of ESS and a good cavity design, no special tight tolerances are required for cavity fabrication and no HOM couplers in the cavity beam pipes are planned.

Export •

reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)