SRF2023 - List of Keywords (laser)

Paper	Title	Other Keywords	Page
MOPMB033	Efforts to Suppress Field Emission in SRF Cavities at KEK	cavity, SRF, acceleration, site	167
	M. Omet, H. Araki, T. Dohmae, H. Ito, R. Katayama, K. Umemori, Y. Yamamoto KEK, Ibaraki, Japan
	Our main objective is to achieve as high as possible quality factors Q₀ and maximal accelerating voltages E_acc within 1.3 GHz superconducting radio frequency (SRF) cavities. Beside an adequate surface treatment, key to achieve good performance is a proper assembly in the clean room prior cavity testing or operation. In this contribution we present the methods and results of our efforts to get a better understanding of our clean room environment and the particulate generation caused during the assembly work. Furthermore, we present the measures taken to suppress filed emission, followed by an analysis of vertical test results of the last six years.
	Poster MOPMB033 [1.532 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB033
About •	Received ※ 14 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 02 September 2023 — Issue date ※ 02 September 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUIAA02	The FLASH 2020+ Upgrade Project	FEL, electron, undulator, operation	354
	M. Vogt, E. Ferrari, C. Gerth, K. Honkavaara, J. Rönsch-Schulenburg, L. Schaper, S. Schreiber, J. Zemella DESY, Hamburg, Germany
	FLASH, the Soft X-Ray and Extreme-UV Free Electron Laser at DESY, is undergoing a substantial upgrade and refurbishment project, called FLASH2020+. The project will finally enable external seeded and SASE FEL operation for a wavelength range down to 4 nm with the EEHG method. A key ingredient of the upgrade was replacing two early TTF-type L-band RF cryo accelerator modules by modern, high-gradient XFEL-type ones. The beam energy range of the injector has been increased by 100 MeV. This was achieved in the first of two long shutdowns from November 2021 to August 2022. The energy increase together with an afterburner APPLE III type undulator for variable circular polarization in the FLASH2 beamline will make it possible to reach the oxygen K-edge (530 eV). This talk will report on the project and the first shutdown with emphasis on the upgraded modules.
	Slides TUIAA02 [15.921 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUIAA02
About •	Received ※ 21 June 2023 — Revised ※ 23 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 07 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPTB049	Horizontal Test Results of 1.3 GHz Superconducting RF Gun #2 at KEK	gun, cavity, cathode, SRF	540
	T. Konomi, K. Hara, Y. Honda, K. Hosoyama, H. Inoue, E. Kako, Y. Kondo, M. Masuzawa, M. Omet, T. Takatomi, A. Terashima, K. Tsuchiya, R. Ueki, K. Umemori, X. Wang KEK, Ibaraki, Japan
	Superconducting radio-frequency (SRF) electron guns are attractive for delivery of beams at a high bunch repetition rate with a high accelerating field. KEK has been developing the SRF gun to demonstrate basic performance. The SRF gun consists of 1.3 GHz and 1.5 cell SRF gun cavity and K2CsSb photocathode coated on 2K cathode plug. In the vertical test, the surface peak electric field and the surface peak magnetic field reached to 75 MV/m and 170 mT respectively. The SRF gun was installed to horizontal multipurpose cryostat equipped with a superconducting solenoid, photocathode preparation chamber and beam diagnostic line. The results showed the peak surface electric field degraded to 42 MV/m. We suspect that cavity was contaminated during assembly. In this presentation, we will present the high gradient performance in vertical and horizontal test and individual test for each beam line components.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB049
About •	Received ※ 24 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 29 June 2023 — Issue date ※ 15 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WECAA01	Progress in European Thin Film Activities	cavity, SRF, target, niobium	607
	C. Pira, O. Azzolini, R. Caforio, E. Chyhyrynets, D. Fonnesu, D. Ford, V.A. Garcia, G. Keppel, G. Marconato, A. Salmaso, F. Stivanello INFN/LNL, Legnaro (PD), Italy C.Z. Antoine, Y. Kalboussi, Th. Proslier CEA-IRFU, Gif-sur-Yvette, France C. Benjamin, O.B. Malyshev, N. Marks, B.S. Sian, R. Valizadeh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom C. Benjamin, J.W. Bradley, G. Burt, O.B. Malyshev, N. Marks, D.J. Seal, B.S. Sian, S. Simon, D.A. Turner, R. Valizadeh Cockcroft Institute, Warrington, Cheshire, United Kingdom S. Berry CEA-DRF-IRFU, France R. Berton, D. Piccoli, F. Piccoli, G. Squizzato, F. Telatin Piccoli, Noale (VE), Italy M. Bertucci, R. Paparella INFN/LASA, Segrate (MI), Italy M. Bonesso, S. Candela, V. Candela, R. Dima, G. Favero, A. Pepato, P. Rebesan, M. Romanato INFN- Sez. di Padova, Padova, Italy J.W. Bradley, S. Simon The University of Liverpool, Liverpool, United Kingdom G. Burt, D.J. Seal, D.A. Turner Lancaster University, Lancaster, United Kingdom O. Hryhorenko, D. Longuevergne Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France X. Jiang, T. Staedler, A.O. Zubtsovskii University Siegen, Siegen, Germany S. Keckert, J. Knobloch, O. Kugeler HZB, Berlin, Germany J. Knobloch University of Siegen, Siegen, Germany N.L. Leicester Cockcroft Institute, Lancaster University, Lancaster, United Kingdom A. Medvids, A. Mychko, P. Onufrijevs Riga Technical University, Riga, Latvia S. Prucnal, S. Zhou HZDR, Dresden, Germany R. Ries Slovak Academy of Sciences, Institute of Electrical Engineering, Bratislava, Slovak Republic E. Seiler IEE, Bratislava, Slovak Republic L.G.P. Smith STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom A-M. Valente-Feliciano JLab, Newport News, Virginia, USA
	Funding: This project has received funding from the European Union s Horizon 2020 Research and Innovation programme under Grant Agreement No 101004730. Thin-film cavities with higher Tc superconductors (SC) than Nb promise to move the operating temperature from 2 to 4.5 K with savings 3 orders of magnitude in cryogenic power consumption. Several European labs are coordinating their efforts to obtain a first 1.3 GHz cavity prototype through the I.FAST collaboration and other informal collaborations with CERN and DESY. R&D covers the entire production chain. In particular, new production techniques of seamless Copper and Niobium elliptical cavities via additive manufacturing are studied and evaluated. New acid-free polishing techniques to reduce surface roughness in a more sustainable way such as plasma electropolishing and metallographic polishing have been tested. Optimization of coating parameters of higher Tc SC than Nb (Nb₃Sn, V₃Si, NbTiN) via PVD and multilayer via ALD are on the way. Finally, rapid heat treatments such as Flash Lamp Annealing and Laser Annealing are used to avoid or reduce Cu diffusion in the SC film. The development and characterization of SC coatings is done on planar samples, 6 GHz cavities, choke cavities, QPR and 1.3 GHz cavities. This work presents the progress status of these coordinated efforts.
	Slides WECAA01 [15.846 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WECAA01
About •	Received ※ 18 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 02 September 2023 — Issue date ※ 02 September 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEIXA06	Recent Advances in Metallographic Polishing for SRF Application	cavity, SRF, niobium, framework	646
	O. Hryhorenko JLab, Newport News, Virginia, USA C.Z. Antoine, F. Éozénou, Th. Proslier Université Paris-Saclay, CEA, Gif-sur-Yvette, France T. Dohmae KEK, Ibaraki, Japan S. Keckert, J. Knobloch, O. Kugeler HZB, Berlin, Germany D. Longuevergne Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
	Funding: ENSAR-2 under grant agreement N° 654002. IFAST under Grant Agreement No 101004730. The U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177. This talk is an overview of the metallographic polishing R&D program covering Niobium and Copper substrates treatment for thin film coating as an alternative fabrication pathway for 1.3 GHz elliptical cavities. The presented research is the result of a collaborative effort between IJCLab, CEA/Irfu, HZB, and KEK in order to develop innovative surface processing and cavity fabrication protocols capable of meeting stringent requirements for SRF surfaces, including the reduction of safety risks and ecological footprint, enhancing reliability, improving the surface roughness, and potentially allowing cost reduction. The research findings will be disclosed.
	Slides WEIXA06 [7.469 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEIXA06
About •	Received ※ 16 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 14 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPWB050	Exploring Innovative Pathway for SRF Cavity Fabrication	cavity, SRF, niobium, electron	680
	O. Hryhorenko JLab, Newport News, Virginia, USA C.Z. Antoine Université Paris-Saclay, CEA, Gif-sur-Yvette, France T. Dohmae KEK, Ibaraki, Japan D. Longuevergne Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France R. Valizadeh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
	Funding: ENSAR-2 under grant agreement N° 654002. The U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177. This article shows a study on an alternative pathway for the fabrication of a complete 1.3 GHz SRF cavity, aiming at improving production reliability, reducing the use of chemical polishing (EP or BCP) which is a costly and safety-critical step, and preserving surface quality after forming. Unlike the conventional pathway, the fabrication process is performed after polishing. This point is crucial as the used polishing technology could be applied only to flat geometries. The performed investigation demonstrates that damages during the fabrication process are considered minor, localized, and limited to the near-surface. Moreover, these studies confirm that the damaged layer (100-200 µm) is mainly caused by the rolling process, and not by the subsequent fabrication steps. A laser confocal microscope and SEM-EBSD technique were used to compare samples before and after forming. The preliminary results are discussed and presented in this paper.
	Poster WEPWB050 [2.263 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB050
About •	Received ※ 20 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 01 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEPWB119	Additive Manufacturing of Pure Niobium and Copper Using Laser Powder Bed Fusion for Particle Accelerator Applications	cavity, niobium, SRF, plasma	872
	D. Ford, R. Caforio, E. Chyhyrynets, G. Keppel, C. Pira INFN/LNL, Legnaro (PD), Italy M. Bonesso, S. Candela, V. Candela, R. Dima, G. Favero, A. Pepato, P. Rebesan, M. Romanato INFN- Sez. di Padova, Padova, Italy M. Pozzi Rösler Italiana s.r.l., Concorezzo, Italy
	Funding: This project has received funding from the European Union¿s Horizon 2020 Research and Innovation programme under Grant Agreement No 101004730. Work supported by the INFN CSNV experiment SAMARA. In this study, Metal Additive Manufacturing (MAM) was evaluated as a viable method for producing seamless 6 GHz pure copper and niobium prototypes without the use of internal supports. Preliminary tests were performed to evaluate printability, leading to further investigations into surface treatments to reduce surface roughness from 35 µm to less than 1 µm. Additional prototypes were printed using different powders and machines, exploring various printing parameters and innovative contactless supporting structures to improve the quality of downward-facing surfaces with small inclination angles. These structures enabled the fabrication of seamless SRF cavities with a relative density greater than 99.8%. Quality testing was conducted using techniques such as tomography, leak testing, resonant frequency assessment, and internal inspection. The results of this study are presented herein.
	Poster WEPWB119 [9.235 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB119
About •	Received ※ 18 June 2023 — Revised ※ 22 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 18 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THIAA01	Development of 3.9 GHz 9-Cell Cavities at SHINE	cavity, electron, linac, FEL	921
	X.W. Wu Zhangjiang Lab, Shanghai, People’s Republic of China J.F. Chen, P.C. Dong, Y.F. Liu, X.H. Ouyang, S. Sun, J.N. Wu, S. Xing, Y.X. Zhang, S.J. Zhao, Y.L. Zhao SARI-CAS, Pudong, Shanghai, People’s Republic of China X. Huang, Z. Wang, Y. Zong SINAP, Shanghai, People’s Republic of China Y.W. Huang, R.Z. Xia ShanghaiTech University, Shanghai, People’s Republic of China
	The Shanghai high-repetition-rate XFEL and extreme light facility (SHINE) Linac requires two 3.9~GHz crymodules to linearize energy distribution before the bunch compressor. As a key component to the project, studies of 3.9~GHz cavities were conducted in the past few years. The first 3.9~GHz 9-cell prototype cavity has been fabricated, tested, and qualified. It reached Q₀=3.5×10⁹ at 13.1~MV/m and a maximum accelerating gradient of 25.0~MV/m during the vertical test of the bare cavity. The prototype has been helium tank integrated and reached Q₀=2.9×10⁹ at 13.1~MV/m in the vertical test, with a large margin with respect to the SHINE specification. The second prototype has been fabricated and is planned to be tested in 2023. This paper will cover the fabrication, surface treatment, and RF test of the 3.9~GHz cavities.
	Slides THIAA01 [7.573 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-THIAA01
About •	Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 18 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

MOPMB033

Efforts to Suppress Field Emission in SRF Cavities at KEK

cavity, SRF, acceleration, site

167

M. Omet, H. Araki, T. Dohmae, H. Ito, R. Katayama, K. Umemori, Y. Yamamoto
KEK, Ibaraki, Japan

Our main objective is to achieve as high as possible quality factors Q₀ and maximal accelerating voltages E_acc within 1.3 GHz superconducting radio frequency (SRF) cavities. Beside an adequate surface treatment, key to achieve good performance is a proper assembly in the clean room prior cavity testing or operation. In this contribution we present the methods and results of our efforts to get a better understanding of our clean room environment and the particulate generation caused during the assembly work. Furthermore, we present the measures taken to suppress filed emission, followed by an analysis of vertical test results of the last six years.

Poster MOPMB033 [1.532 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB033

About •

Received ※ 14 June 2023 — Revised ※ 25 June 2023 — Accepted ※ 02 September 2023 — Issue date ※ 02 September 2023

Cite •

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

TUIAA02

The FLASH 2020+ Upgrade Project

FEL, electron, undulator, operation

354

M. Vogt, E. Ferrari, C. Gerth, K. Honkavaara, J. Rönsch-Schulenburg, L. Schaper, S. Schreiber, J. Zemella
DESY, Hamburg, Germany

FLASH, the Soft X-Ray and Extreme-UV Free Electron Laser at DESY, is undergoing a substantial upgrade and refurbishment project, called FLASH2020+. The project will finally enable external seeded and SASE FEL operation for a wavelength range down to 4 nm with the EEHG method. A key ingredient of the upgrade was replacing two early TTF-type L-band RF cryo accelerator modules by modern, high-gradient XFEL-type ones. The beam energy range of the injector has been increased by 100 MeV. This was achieved in the first of two long shutdowns from November 2021 to August 2022. The energy increase together with an afterburner APPLE III type undulator for variable circular polarization in the FLASH2 beamline will make it possible to reach the oxygen K-edge (530 eV). This talk will report on the project and the first shutdown with emphasis on the upgraded modules.

Slides TUIAA02 [15.921 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUIAA02

About •

Received ※ 21 June 2023 — Revised ※ 23 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 07 July 2023

Cite •

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

TUPTB049

Horizontal Test Results of 1.3 GHz Superconducting RF Gun #2 at KEK

gun, cavity, cathode, SRF

540

T. Konomi, K. Hara, Y. Honda, K. Hosoyama, H. Inoue, E. Kako, Y. Kondo, M. Masuzawa, M. Omet, T. Takatomi, A. Terashima, K. Tsuchiya, R. Ueki, K. Umemori, X. Wang
KEK, Ibaraki, Japan

Superconducting radio-frequency (SRF) electron guns are attractive for delivery of beams at a high bunch repetition rate with a high accelerating field. KEK has been developing the SRF gun to demonstrate basic performance. The SRF gun consists of 1.3 GHz and 1.5 cell SRF gun cavity and K2CsSb photocathode coated on 2K cathode plug. In the vertical test, the surface peak electric field and the surface peak magnetic field reached to 75 MV/m and 170 mT respectively. The SRF gun was installed to horizontal multipurpose cryostat equipped with a superconducting solenoid, photocathode preparation chamber and beam diagnostic line. The results showed the peak surface electric field degraded to 42 MV/m. We suspect that cavity was contaminated during assembly. In this presentation, we will present the high gradient performance in vertical and horizontal test and individual test for each beam line components.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB049

About •

Received ※ 24 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 29 June 2023 — Issue date ※ 15 July 2023

Cite •

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

WECAA01

Progress in European Thin Film Activities

cavity, SRF, target, niobium

607

C. Pira, O. Azzolini, R. Caforio, E. Chyhyrynets, D. Fonnesu, D. Ford, V.A. Garcia, G. Keppel, G. Marconato, A. Salmaso, F. Stivanello
INFN/LNL, Legnaro (PD), Italy
C.Z. Antoine, Y. Kalboussi, Th. Proslier
CEA-IRFU, Gif-sur-Yvette, France
C. Benjamin, O.B. Malyshev, N. Marks, B.S. Sian, R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
C. Benjamin, J.W. Bradley, G. Burt, O.B. Malyshev, N. Marks, D.J. Seal, B.S. Sian, S. Simon, D.A. Turner, R. Valizadeh
Cockcroft Institute, Warrington, Cheshire, United Kingdom
S. Berry
CEA-DRF-IRFU, France
R. Berton, D. Piccoli, F. Piccoli, G. Squizzato, F. Telatin
Piccoli, Noale (VE), Italy
M. Bertucci, R. Paparella
INFN/LASA, Segrate (MI), Italy
M. Bonesso, S. Candela, V. Candela, R. Dima, G. Favero, A. Pepato, P. Rebesan, M. Romanato
INFN- Sez. di Padova, Padova, Italy
J.W. Bradley, S. Simon
The University of Liverpool, Liverpool, United Kingdom
G. Burt, D.J. Seal, D.A. Turner
Lancaster University, Lancaster, United Kingdom
O. Hryhorenko, D. Longuevergne
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
X. Jiang, T. Staedler, A.O. Zubtsovskii
University Siegen, Siegen, Germany
S. Keckert, J. Knobloch, O. Kugeler
HZB, Berlin, Germany
J. Knobloch
University of Siegen, Siegen, Germany
N.L. Leicester
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
A. Medvids, A. Mychko, P. Onufrijevs
Riga Technical University, Riga, Latvia
S. Prucnal, S. Zhou
HZDR, Dresden, Germany
R. Ries
Slovak Academy of Sciences, Institute of Electrical Engineering, Bratislava, Slovak Republic
E. Seiler
IEE, Bratislava, Slovak Republic
L.G.P. Smith
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
A-M. Valente-Feliciano
JLab, Newport News, Virginia, USA

Funding: This project has received funding from the European Union s Horizon 2020 Research and Innovation programme under Grant Agreement No 101004730.
Thin-film cavities with higher Tc superconductors (SC) than Nb promise to move the operating temperature from 2 to 4.5 K with savings 3 orders of magnitude in cryogenic power consumption. Several European labs are coordinating their efforts to obtain a first 1.3 GHz cavity prototype through the I.FAST collaboration and other informal collaborations with CERN and DESY. R&D covers the entire production chain. In particular, new production techniques of seamless Copper and Niobium elliptical cavities via additive manufacturing are studied and evaluated. New acid-free polishing techniques to reduce surface roughness in a more sustainable way such as plasma electropolishing and metallographic polishing have been tested. Optimization of coating parameters of higher Tc SC than Nb (Nb₃Sn, V₃Si, NbTiN) via PVD and multilayer via ALD are on the way. Finally, rapid heat treatments such as Flash Lamp Annealing and Laser Annealing are used to avoid or reduce Cu diffusion in the SC film. The development and characterization of SC coatings is done on planar samples, 6 GHz cavities, choke cavities, QPR and 1.3 GHz cavities. This work presents the progress status of these coordinated efforts.

Slides WECAA01 [15.846 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WECAA01

About •

Received ※ 18 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 02 September 2023 — Issue date ※ 02 September 2023

Cite •

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

WEIXA06

Recent Advances in Metallographic Polishing for SRF Application

cavity, SRF, niobium, framework

646

O. Hryhorenko
JLab, Newport News, Virginia, USA
C.Z. Antoine, F. Éozénou, Th. Proslier
Université Paris-Saclay, CEA, Gif-sur-Yvette, France
T. Dohmae
KEK, Ibaraki, Japan
S. Keckert, J. Knobloch, O. Kugeler
HZB, Berlin, Germany
D. Longuevergne
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France

Funding: ENSAR-2 under grant agreement N° 654002. IFAST under Grant Agreement No 101004730. The U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
This talk is an overview of the metallographic polishing R&D program covering Niobium and Copper substrates treatment for thin film coating as an alternative fabrication pathway for 1.3 GHz elliptical cavities. The presented research is the result of a collaborative effort between IJCLab, CEA/Irfu, HZB, and KEK in order to develop innovative surface processing and cavity fabrication protocols capable of meeting stringent requirements for SRF surfaces, including the reduction of safety risks and ecological footprint, enhancing reliability, improving the surface roughness, and potentially allowing cost reduction. The research findings will be disclosed.

Slides WEIXA06 [7.469 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEIXA06

About •

Received ※ 16 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 14 July 2023

Cite •

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

WEPWB050

Exploring Innovative Pathway for SRF Cavity Fabrication

cavity, SRF, niobium, electron

680

O. Hryhorenko
JLab, Newport News, Virginia, USA
C.Z. Antoine
Université Paris-Saclay, CEA, Gif-sur-Yvette, France
T. Dohmae
KEK, Ibaraki, Japan
D. Longuevergne
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom

Funding: ENSAR-2 under grant agreement N° 654002. The U.S. Department of Energy, Office of Science, Office of Nuclear Physics under contract DE-AC05-06OR23177.
This article shows a study on an alternative pathway for the fabrication of a complete 1.3 GHz SRF cavity, aiming at improving production reliability, reducing the use of chemical polishing (EP or BCP) which is a costly and safety-critical step, and preserving surface quality after forming. Unlike the conventional pathway, the fabrication process is performed after polishing. This point is crucial as the used polishing technology could be applied only to flat geometries. The performed investigation demonstrates that damages during the fabrication process are considered minor, localized, and limited to the near-surface. Moreover, these studies confirm that the damaged layer (100-200 µm) is mainly caused by the rolling process, and not by the subsequent fabrication steps. A laser confocal microscope and SEM-EBSD technique were used to compare samples before and after forming. The preliminary results are discussed and presented in this paper.

Poster WEPWB050 [2.263 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB050

About •

Received ※ 20 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 01 July 2023

Cite •

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

WEPWB119

Additive Manufacturing of Pure Niobium and Copper Using Laser Powder Bed Fusion for Particle Accelerator Applications

cavity, niobium, SRF, plasma

872

D. Ford, R. Caforio, E. Chyhyrynets, G. Keppel, C. Pira
INFN/LNL, Legnaro (PD), Italy
M. Bonesso, S. Candela, V. Candela, R. Dima, G. Favero, A. Pepato, P. Rebesan, M. Romanato
INFN- Sez. di Padova, Padova, Italy
M. Pozzi
Rösler Italiana s.r.l., Concorezzo, Italy

Funding: This project has received funding from the European Union¿s Horizon 2020 Research and Innovation programme under Grant Agreement No 101004730. Work supported by the INFN CSNV experiment SAMARA.
In this study, Metal Additive Manufacturing (MAM) was evaluated as a viable method for producing seamless 6 GHz pure copper and niobium prototypes without the use of internal supports. Preliminary tests were performed to evaluate printability, leading to further investigations into surface treatments to reduce surface roughness from 35 µm to less than 1 µm. Additional prototypes were printed using different powders and machines, exploring various printing parameters and innovative contactless supporting structures to improve the quality of downward-facing surfaces with small inclination angles. These structures enabled the fabrication of seamless SRF cavities with a relative density greater than 99.8%. Quality testing was conducted using techniques such as tomography, leak testing, resonant frequency assessment, and internal inspection. The results of this study are presented herein.

Poster WEPWB119 [9.235 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB119

About •

Received ※ 18 June 2023 — Revised ※ 22 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 18 July 2023

Cite •

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

THIAA01

Development of 3.9 GHz 9-Cell Cavities at SHINE

cavity, electron, linac, FEL

921

X.W. Wu
Zhangjiang Lab, Shanghai, People’s Republic of China
J.F. Chen, P.C. Dong, Y.F. Liu, X.H. Ouyang, S. Sun, J.N. Wu, S. Xing, Y.X. Zhang, S.J. Zhao, Y.L. Zhao
SARI-CAS, Pudong, Shanghai, People’s Republic of China
X. Huang, Z. Wang, Y. Zong
SINAP, Shanghai, People’s Republic of China
Y.W. Huang, R.Z. Xia
ShanghaiTech University, Shanghai, People’s Republic of China

The Shanghai high-repetition-rate XFEL and extreme light facility (SHINE) Linac requires two 3.9~GHz crymodules to linearize energy distribution before the bunch compressor. As a key component to the project, studies of 3.9~GHz cavities were conducted in the past few years. The first 3.9~GHz 9-cell prototype cavity has been fabricated, tested, and qualified. It reached Q₀=3.5×10⁹ at 13.1~MV/m and a maximum accelerating gradient of 25.0~MV/m during the vertical test of the bare cavity. The prototype has been helium tank integrated and reached Q₀=2.9×10⁹ at 13.1~MV/m in the vertical test, with a large margin with respect to the SHINE specification. The second prototype has been fabricated and is planned to be tested in 2023. This paper will cover the fabrication, surface treatment, and RF test of the 3.9~GHz cavities.

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DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-THIAA01

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Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 18 July 2023

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