SRF2013 - List of Authors (Laasch, R.)

Paper	Title	Page
MOP043	ILC-HiGrade Cavities as a Tool of Quality Control for European XFEL	212
	A. Navitski, E. Elsen, B. Foster, J. Iversen, A. Matheisen, D. Reschke, W. Singer, X. Singer, L. Steder, M. Wenskat DESY, Hamburg, Germany R. Laasch, Y. Tamashevich University of Hamburg, Hamburg, Germany
	Funding: BMBF, Helmholtz Association, ILC-HiGrade, FP7 (CRISP), Alexander von Humboldt Stiftung/Foundation The EXFEL order for SRF cavities includes 24 cavities, which are part of the ILC-HiGrade program. Initially, these cavities serve as quality control (QC) sample extracted from the EXFEL cavities series production on a regular basis. The QC and quality assurance (QA) include all processing steps of the EXFEL cavities. To maximize the information from these so-called QC cavities, a surface mapping technique is applied in a second cold RF test. There the cavities delivered have experienced identical treatment of the inner surface with the exception of mounting of the Helium vessel. After the normal acceptance test at the cavity RF measurement facility, the cavities are removed from the production flow. Further quality assurance steps beginning with a detailed RF test with surface mapping followed by a high resolution optical inspection (OBACHT) are carried out to improve the understanding of defects in close collaboration with the standing experts engaged in the EXFEL production. Results of the first QC cavities tests as well as planned further R&D will be presented and discussed.

MOP053	R&D on Cavity Treatments at DESY Towards the ILC Performance Goal	240
	A. Navitski, E. Elsen, B. Foster, D. Reschke, J. Schaffran, W. Singer, X. Singer DESY, Hamburg, Germany R. Laasch, Y. Tamashevich University of Hamburg, Hamburg, Germany
	Funding: BMBF, Helmholtz Association, ILC-HiGrade, FP7 (CRISP), Alexander von Humboldt Stiftung/Foundation The actual R&D program at DESY is derived from the global effort for the International Linear Collider (ILC) and is well in phase with effort elsewhere. The program aims at a solid understanding and control of the industrial mass-production process of the superconducting radio-frequency accelerating cavities, which are manufactured for the European X-ray Free Electron Laser (EXFEL) at DESY. The goal is to identify the gradient limiting factors and further refine the cavity treatment technique to provide gradients above 35 MV/m at >90% production yield. Techniques such as 2nd sound quench detection, OBACHT optical inspections, defect metrology using silicon replica as well as Centrifugal Barrel Polishing (CBP) and Local Grinding repair are foreseen as tools. Actual status, details, and first achievements of the program will be reported.

Paper

Title

Page

ILC-HiGrade Cavities as a Tool of Quality Control for European XFEL

212

A. Navitski, E. Elsen, B. Foster, J. Iversen, A. Matheisen, D. Reschke, W. Singer, X. Singer, L. Steder, M. Wenskat
DESY, Hamburg, Germany
R. Laasch, Y. Tamashevich
University of Hamburg, Hamburg, Germany

Funding: BMBF, Helmholtz Association, ILC-HiGrade, FP7 (CRISP), Alexander von Humboldt Stiftung/Foundation
The EXFEL order for SRF cavities includes 24 cavities, which are part of the ILC-HiGrade program. Initially, these cavities serve as quality control (QC) sample extracted from the EXFEL cavities series production on a regular basis. The QC and quality assurance (QA) include all processing steps of the EXFEL cavities. To maximize the information from these so-called QC cavities, a surface mapping technique is applied in a second cold RF test. There the cavities delivered have experienced identical treatment of the inner surface with the exception of mounting of the Helium vessel. After the normal acceptance test at the cavity RF measurement facility, the cavities are removed from the production flow. Further quality assurance steps beginning with a detailed RF test with surface mapping followed by a high resolution optical inspection (OBACHT) are carried out to improve the understanding of defects in close collaboration with the standing experts engaged in the EXFEL production. Results of the first QC cavities tests as well as planned further R&D will be presented and discussed.

MOP053

R&D on Cavity Treatments at DESY Towards the ILC Performance Goal

240

A. Navitski, E. Elsen, B. Foster, D. Reschke, J. Schaffran, W. Singer, X. Singer
DESY, Hamburg, Germany
R. Laasch, Y. Tamashevich
University of Hamburg, Hamburg, Germany

Funding: BMBF, Helmholtz Association, ILC-HiGrade, FP7 (CRISP), Alexander von Humboldt Stiftung/Foundation
The actual R&D program at DESY is derived from the global effort for the International Linear Collider (ILC) and is well in phase with effort elsewhere. The program aims at a solid understanding and control of the industrial mass-production process of the superconducting radio-frequency accelerating cavities, which are manufactured for the European X-ray Free Electron Laser (EXFEL) at DESY. The goal is to identify the gradient limiting factors and further refine the cavity treatment technique to provide gradients above 35 MV/m at >90% production yield. Techniques such as 2nd sound quench detection, OBACHT optical inspections, defect metrology using silicon replica as well as Centrifugal Barrel Polishing (CBP) and Local Grinding repair are foreseen as tools. Actual status, details, and first achievements of the program will be reported.