SRF2017 - List of Keywords (pick-up)

Paper	Title	Other Keywords	Page
MOPB037	Progress of the 2x4-Cell Superconducting Accelerator for the CAEP THz-FEL Facility	ion, cavity, cryomodule, cryogenics	134
	K. Zhou, C.L. Lao, M. Li, X. Luo, L.J. Shan, X. Shen, H. Wang, X. Yang CAEP/IAE, Mianyang, Sichuan, People's Republic of China X.Y. Lu PKU, Beijing, People's Republic of China
	The high average power THz radiation facility is now under construction in China Academy of Engineering Physics. The superconducting accelerator is one of the most important components for this facility, including two 4-Cell TESLA superconducting radio frequency cavities. The designed effective field gradients for both cavities are 10^-12 MV/m. This paper will present the progress of the 2x4-cell superconducting accelerator, mainly including its construction and cryogenic test in Chengdu. At 2 K state, the cryomodule works smoothly and stably. The effective field gradients of both cavities have achieved 10 MV/m. Further beam loading experiments are now in progress.
	Poster MOPB037 [5.124 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB037
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MOPB088	Experience on In-situ Module Repair and Set Up of Non XFEL Cavity Strings at DESY	ion, cavity, FEL, HOM	269
	M. Schmökel, A. Daniel, N. Krupka, A. Matheisen, S. Saegebarth, M. Schalwat, P. Schilling DESY, Hamburg, Germany
	All components installed to the European XFEL cavity string modules underwent an intensive inspection and quality control before acceptance for installation to cavities or modules. Even though some RF feed throughs for HOM coupler- and Pick Up antennas showed leaks at the ceramic insulation after module test at 2 K. Due to time restriction and continuity of production the exchange of these parts needed to be done without reentering the cleanroom. Successful repair of these modules took place by setting up a local cleanroom onto the cavity string. In collaboration with Helmholtz-Zentrum Dresden-Rossendorf (HZDR), a cavity string for the ELBE project was assembled at DESY and transported to HZDR for installation to the vacuum vessel. A spare module with 3.9 GHz Resonators for the European XFEL was set up at DESY and will be tested and qualified for the European XFEL. Due to delay in delivery of the power couplers, four power couplers were installed after string assembly.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB088
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TUPB010	Multipactor Study in the Coupler Region of the Diamond SCRF Cavities	ion, cavity, GUI, electron	405
	S.A. Pande, C. Christou, P. Gu DLS, Oxfordshire, United Kingdom G. Burt Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
	The Diamond storage ring operates with two CESR-B type Superconducting RF cavities. The cavities suffer from trips with a sudden loss of accelerating field if operated above a certain voltage. Consequently the cavities are operated at voltages up to 1.4 MV for better reliability. These cavities are iris coupled and have fixed Qext. At these lower operating voltages, the optimum condition for beam loading is satisfied at powers around 100 kW. For operation at 300 mA with two cavities, the power needed per system exceeds 200 kW. Therefore 3 stub tuners are used to lower the Qext to move the optimum condition close to 200kW. Additionally, the step due to the difference in the height of the coupling waveguide on the cavity and that of the vacuum side waveguide on the window results in a standing wave between the cavity and the window even at matched operation. The 3 stub tuner further enhances this standing wave. Numerical simulation reveals that the standing wave field from the cavity penetrates into the coupling waveguide increasing the probability of multipactor and breakdown in the coupler region. The results of multipactor simulations in this region with CST Studio are discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB010
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TUPB023	Further Tests on the SC 325 MHz CH-cavity and Power Coupler Test Setup	ion, cavity, linac, SRF	437
	M. Busch, M. Basten, H. Podlech, U. Ratzinger, M. Schwarz IAP, Frankfurt am Main, Germany W.A. Barth MEPhI, Moscow, Russia W.A. Barth GSI, Darmstadt, Germany W.A. Barth, F.D. Dziuba, V. Gettmann HIM, Mainz, Germany
	Funding: Work supported by BMBF contr. No. 05P15RFRBA The 325MHz CH-cavity which has been developed and successfully vertically tested at the Institute for Applied Physics, Frankfurt, has has been welded to the helium vessel at the frontal joints of the cavity and further vertical and horizontal tests are in preparation. Finally a beam test with a 11.4 AMeV, 10 mA ion beam at GSI, Darmstadt is projected. Furthermore a newly developed, dedicated test stand for the 217 MHz power couplers has been set up for the cavities of the sc cw-LINAC project at GSI.
	Poster TUPB023 [2.579 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB023
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPB037

Progress of the 2x4-Cell Superconducting Accelerator for the CAEP THz-FEL Facility

ion, cavity, cryomodule, cryogenics

134

K. Zhou, C.L. Lao, M. Li, X. Luo, L.J. Shan, X. Shen, H. Wang, X. Yang
CAEP/IAE, Mianyang, Sichuan, People's Republic of China
X.Y. Lu
PKU, Beijing, People's Republic of China

The high average power THz radiation facility is now under construction in China Academy of Engineering Physics. The superconducting accelerator is one of the most important components for this facility, including two 4-Cell TESLA superconducting radio frequency cavities. The designed effective field gradients for both cavities are 10^-12 MV/m. This paper will present the progress of the 2x4-cell superconducting accelerator, mainly including its construction and cryogenic test in Chengdu. At 2 K state, the cryomodule works smoothly and stably. The effective field gradients of both cavities have achieved 10 MV/m. Further beam loading experiments are now in progress.

Poster MOPB037 [5.124 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB037

Export •

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

MOPB088

Experience on In-situ Module Repair and Set Up of Non XFEL Cavity Strings at DESY

ion, cavity, FEL, HOM

269

M. Schmökel, A. Daniel, N. Krupka, A. Matheisen, S. Saegebarth, M. Schalwat, P. Schilling
DESY, Hamburg, Germany

All components installed to the European XFEL cavity string modules underwent an intensive inspection and quality control before acceptance for installation to cavities or modules. Even though some RF feed throughs for HOM coupler- and Pick Up antennas showed leaks at the ceramic insulation after module test at 2 K. Due to time restriction and continuity of production the exchange of these parts needed to be done without reentering the cleanroom. Successful repair of these modules took place by setting up a local cleanroom onto the cavity string. In collaboration with Helmholtz-Zentrum Dresden-Rossendorf (HZDR), a cavity string for the ELBE project was assembled at DESY and transported to HZDR for installation to the vacuum vessel. A spare module with 3.9 GHz Resonators for the European XFEL was set up at DESY and will be tested and qualified for the European XFEL. Due to delay in delivery of the power couplers, four power couplers were installed after string assembly.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-MOPB088

Export •

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

TUPB010

Multipactor Study in the Coupler Region of the Diamond SCRF Cavities

ion, cavity, GUI, electron

405

S.A. Pande, C. Christou, P. Gu
DLS, Oxfordshire, United Kingdom
G. Burt
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom

The Diamond storage ring operates with two CESR-B type Superconducting RF cavities. The cavities suffer from trips with a sudden loss of accelerating field if operated above a certain voltage. Consequently the cavities are operated at voltages up to 1.4 MV for better reliability. These cavities are iris coupled and have fixed Qext. At these lower operating voltages, the optimum condition for beam loading is satisfied at powers around 100 kW. For operation at 300 mA with two cavities, the power needed per system exceeds 200 kW. Therefore 3 stub tuners are used to lower the Qext to move the optimum condition close to 200kW. Additionally, the step due to the difference in the height of the coupling waveguide on the cavity and that of the vacuum side waveguide on the window results in a standing wave between the cavity and the window even at matched operation. The 3 stub tuner further enhances this standing wave. Numerical simulation reveals that the standing wave field from the cavity penetrates into the coupling waveguide increasing the probability of multipactor and breakdown in the coupler region. The results of multipactor simulations in this region with CST Studio are discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB010

Export •

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

TUPB023

Further Tests on the SC 325 MHz CH-cavity and Power Coupler Test Setup

ion, cavity, linac, SRF

437

M. Busch, M. Basten, H. Podlech, U. Ratzinger, M. Schwarz
IAP, Frankfurt am Main, Germany
W.A. Barth
MEPhI, Moscow, Russia
W.A. Barth
GSI, Darmstadt, Germany
W.A. Barth, F.D. Dziuba, V. Gettmann
HIM, Mainz, Germany

Funding: Work supported by BMBF contr. No. 05P15RFRBA
The 325MHz CH-cavity which has been developed and successfully vertically tested at the Institute for Applied Physics, Frankfurt, has has been welded to the helium vessel at the frontal joints of the cavity and further vertical and horizontal tests are in preparation. Finally a beam test with a 11.4 AMeV, 10 mA ion beam at GSI, Darmstadt is projected. Furthermore a newly developed, dedicated test stand for the 217 MHz power couplers has been set up for the cavities of the sc cw-LINAC project at GSI.

Poster TUPB023 [2.579 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB023

Export •

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