LINAC2018 - List of Keywords (superconducting-cavity)

Paper	Title	Other Keywords	Page
MOPO120	Improvement of the Linear Part in the Tuner System of ADS 25 MeV Linac	linac, experiment, proton, cavity	250
	L. Zhang, Z. Gao, L.B. Liu, F.F. Wang, B. Zhang IMP/CAS, Lanzhou, People’s Republic of China
	Tuner system is the indispensable part of ADS high current proton superconducting linac. It influences the working frequency of superconducting cavity of particle accelerator. To completely understand the working situa-tion of the tuner system and analyses the problems existing in it, experiments of linear part were fully conducted.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO120
About •	paper received ※ 09 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPO035	Determination of the Field-dependence of the Surface Resistance of Superconductors from Cavity Tests	cavity, experiment, electromagnetic-fields, SRF	405
	J.R. Delayen, S.U. De Silva, H. Park ODU, Norfolk, Virginia, USA
	Cryogenic tests of superconducting cavities yield an average surface resistance as a function of the peak surface magnetic field. An analytical formalism has been developed to extract the actual field dependence of the surface resistance from cavity tests and is applied to coaxial cavities and cavities of more complex geometries.
	Slides TUPO035 [0.524 MB]
	Poster TUPO035 [1.002 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO035
About •	paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
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TUPO049	Nitrogen Doping Study With 1.3 GHz Single Cell Superconducting Cavities	cavity, vacuum, accelerating-gradient, niobium	442
	S. Chen, M. Chen, L.W. Feng, J.K. Hao, L. Lin, K.X. Liu, S.W. Quan, F. Wang, F. Zhu PKU, Beijing, People’s Republic of China
	Nitrogen doping studies were carried out at Peking University. A series of 1.3 GHz single cell cavities fabricated with OTIC large grain niobium material were annealed and doped in the furnace of Peking University, and electropolished by a simple EP device. Light doping recipe and heavy doping recipe are both adopted for comparison. The results and analysis are presented in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO049
About •	paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPO051	Design Considerations of a Balloon-shaped SSR Superconducting Cavity	cavity, simulation, electron, distributed	448
	H.J. Cha, S.W. Jang, E.-S. Kim, K.R. Kim, S. H. Park, J.Y. Yoon Korea University Sejong Campus, Sejong, Republic of Korea
	A single spoke resonator (SSR, β = 0.51 and f = 325 MHz) is being developed at Korea University. It is well-known that a traditional spoke cavity having flat or round end walls has broad multipacting ranges in acceleration gradient, sometimes including operation region. In general, quite long conditioning time is consumed to overcome such multipacting barriers. In this study, we introduce a balloon-shaped SSR superconducting cavity for the multipacting mitigation due to structural simplicity. The electromagnetic modeling of the SSR was made based on the RF parameter optimization. The simulation results show much narrower multipacting bandwidth, compared to those for the traditional spoke cavity. Mechanical analyses with stiffening structure at maximum allowable working pressures indicate acceptable stresses at the SSR cavity wall. In addition, the resonant frequency shifts due to fabrication and processing for cold tests are predicted and power coupling and tuning mechanism are also investigated.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO051
About •	paper received ※ 10 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPO052	Design Study of a Prototype 325MHz RF Power Coupler for Superconducting Cavity	simulation, pick-up, cavity, resonance	451
	J.Y. Yoon, J.B. Bhang, H.J. Cha, S.W. Jang, E.-S. Kim, K.R. Kim, C.S. Park, S. H. Park Korea University Sejong Campus, Sejong, Republic of Korea E. Kako KEK, Ibaraki, Japan D.Y. Kim, J. Lee Vitzrotech Co., Ltd., Ansan City, Kyunggi-Do, Republic of Korea I. Shin IBS, Daejeon, Republic of Korea
	Funding: Korea University (Sejong Campus) in South KOREA We present design studies of a prototype RF input power coupler, which provides RF powers to 325MHz cavities up to 18.5 kW in CW mode. The prototype power coupler is a coaxial capacitive type with single ceramic window. In order to optimize the RF coupler design, we performed multi-physics simulations, including electromagnetic, thermal, and mechanical analyses.
	Poster TUPO052 [1.607 MB]
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO052
About •	paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPO053	Fabrication of Nb Mushroom Shaped Cavity for Evaluation of Multi-layer Thin-film Superconductor	cavity, vacuum, electromagnetic-fields, cryogenics	454
	H. Oikawa Utsunomiya University, Utsunomiya, Japan K. Enami, H. Hayano, H. Inoue KEK, Ibaraki, Japan T. Higashiguchi Center for Optical Research and Education, Utsunomiya University, Utsunomiya, Japan
	The accelerating gradient of the Nb superconducting RF cavity seems to reach the limit due to the RF critical magnetic field of the Nb material. To obtain more higher gradient, there has been proposed a method of increasing an RF critical magnetic field of the cavity inner surface by coating of multi-layer thin-film superconductor. It is needed to demonstrate improvement RF critical magnetic field of the RF cavity coated with multi-layer thin-film superconductor. To optimize thin-film superconductor, sample tests are required. A cavity for sample test is necessary to produce a strong RF magnetic field parallel to the surface of the sample for evaluating RF critical magnetic field. For such a cavity, we designed a mushroom shaped cavity made of Nb which is operated in cryogenic temperature. Input and pick up antenna coupler are also designed electrically and mechanically. The connection design of sample plate and cavity bottom plate in superconducting state is also designed. The Nb mushroom shaped cavity is under fabrication. Fabrication method and status are reported in this paper.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO053
About •	paper received ※ 17 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPO120

Improvement of the Linear Part in the Tuner System of ADS 25 MeV Linac

linac, experiment, proton, cavity

250

L. Zhang, Z. Gao, L.B. Liu, F.F. Wang, B. Zhang
IMP/CAS, Lanzhou, People’s Republic of China

Tuner system is the indispensable part of ADS high current proton superconducting linac. It influences the working frequency of superconducting cavity of particle accelerator. To completely understand the working situa-tion of the tuner system and analyses the problems existing in it, experiments of linear part were fully conducted.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-MOPO120

About •

paper received ※ 09 September 2018 paper accepted ※ 21 September 2018 issue date ※ 18 January 2019

Export •

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

TUPO035

Determination of the Field-dependence of the Surface Resistance of Superconductors from Cavity Tests

cavity, experiment, electromagnetic-fields, SRF

405

J.R. Delayen, S.U. De Silva, H. Park
ODU, Norfolk, Virginia, USA

Cryogenic tests of superconducting cavities yield an average surface resistance as a function of the peak surface magnetic field. An analytical formalism has been developed to extract the actual field dependence of the surface resistance from cavity tests and is applied to coaxial cavities and cavities of more complex geometries.

Slides TUPO035 [0.524 MB]

Poster TUPO035 [1.002 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO035

About •

paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

Export •

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

TUPO049

Nitrogen Doping Study With 1.3 GHz Single Cell Superconducting Cavities

cavity, vacuum, accelerating-gradient, niobium

442

S. Chen, M. Chen, L.W. Feng, J.K. Hao, L. Lin, K.X. Liu, S.W. Quan, F. Wang, F. Zhu
PKU, Beijing, People’s Republic of China

Nitrogen doping studies were carried out at Peking University. A series of 1.3 GHz single cell cavities fabricated with OTIC large grain niobium material were annealed and doped in the furnace of Peking University, and electropolished by a simple EP device. Light doping recipe and heavy doping recipe are both adopted for comparison. The results and analysis are presented in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO049

About •

paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

Export •

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

TUPO051

Design Considerations of a Balloon-shaped SSR Superconducting Cavity

cavity, simulation, electron, distributed

448

H.J. Cha, S.W. Jang, E.-S. Kim, K.R. Kim, S. H. Park, J.Y. Yoon
Korea University Sejong Campus, Sejong, Republic of Korea

A single spoke resonator (SSR, β = 0.51 and f = 325 MHz) is being developed at Korea University. It is well-known that a traditional spoke cavity having flat or round end walls has broad multipacting ranges in acceleration gradient, sometimes including operation region. In general, quite long conditioning time is consumed to overcome such multipacting barriers. In this study, we introduce a balloon-shaped SSR superconducting cavity for the multipacting mitigation due to structural simplicity. The electromagnetic modeling of the SSR was made based on the RF parameter optimization. The simulation results show much narrower multipacting bandwidth, compared to those for the traditional spoke cavity. Mechanical analyses with stiffening structure at maximum allowable working pressures indicate acceptable stresses at the SSR cavity wall. In addition, the resonant frequency shifts due to fabrication and processing for cold tests are predicted and power coupling and tuning mechanism are also investigated.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO051

About •

paper received ※ 10 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

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

TUPO052

Design Study of a Prototype 325MHz RF Power Coupler for Superconducting Cavity

simulation, pick-up, cavity, resonance

451

J.Y. Yoon, J.B. Bhang, H.J. Cha, S.W. Jang, E.-S. Kim, K.R. Kim, C.S. Park, S. H. Park
Korea University Sejong Campus, Sejong, Republic of Korea
E. Kako
KEK, Ibaraki, Japan
D.Y. Kim, J. Lee
Vitzrotech Co., Ltd., Ansan City, Kyunggi-Do, Republic of Korea
I. Shin
IBS, Daejeon, Republic of Korea

Funding: Korea University (Sejong Campus) in South KOREA
We present design studies of a prototype RF input power coupler, which provides RF powers to 325MHz cavities up to 18.5 kW in CW mode. The prototype power coupler is a coaxial capacitive type with single ceramic window. In order to optimize the RF coupler design, we performed multi-physics simulations, including electromagnetic, thermal, and mechanical analyses.

Poster TUPO052 [1.607 MB]

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO052

About •

paper received ※ 12 September 2018 paper accepted ※ 19 September 2018 issue date ※ 18 January 2019

Export •

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

TUPO053

Fabrication of Nb Mushroom Shaped Cavity for Evaluation of Multi-layer Thin-film Superconductor

cavity, vacuum, electromagnetic-fields, cryogenics

454

H. Oikawa
Utsunomiya University, Utsunomiya, Japan
K. Enami, H. Hayano, H. Inoue
KEK, Ibaraki, Japan
T. Higashiguchi
Center for Optical Research and Education, Utsunomiya University, Utsunomiya, Japan

The accelerating gradient of the Nb superconducting RF cavity seems to reach the limit due to the RF critical magnetic field of the Nb material. To obtain more higher gradient, there has been proposed a method of increasing an RF critical magnetic field of the cavity inner surface by coating of multi-layer thin-film superconductor. It is needed to demonstrate improvement RF critical magnetic field of the RF cavity coated with multi-layer thin-film superconductor. To optimize thin-film superconductor, sample tests are required. A cavity for sample test is necessary to produce a strong RF magnetic field parallel to the surface of the sample for evaluating RF critical magnetic field. For such a cavity, we designed a mushroom shaped cavity made of Nb which is operated in cryogenic temperature. Input and pick up antenna coupler are also designed electrically and mechanically. The connection design of sample plate and cavity bottom plate in superconducting state is also designed. The Nb mushroom shaped cavity is under fabrication. Fabrication method and status are reported in this paper.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-LINAC2018-TUPO053

About •

paper received ※ 17 September 2018 paper accepted ※ 20 September 2018 issue date ※ 18 January 2019

Export •

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