IPAC2015 - List of Authors (Facco, A.)

Paper	Title	Page
WEPTY060	Virtual Welding as a Tool for Superconducting Cavity Coarse Tuning	3412
	A. Facco, C. Compton, J. Popielarski, G.J. Velianoff FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 Reaching the final frequency in the construction of Superconducting Half-Wave Resonators (HWR), either coaxial or spoke, is often a painful and time consuming process which requires several intermediate frequency tests and parts machining between subsequent welding steps. In spite of that, the final frequency error after final welding is often far from the target due to difficult to predict material contraction and cavity deformation induced by electron beam welding (EBW). Final coarse tuning is required by plastic deformation or differential etching. In coaxial HWR, both can decrease the cavity frequency but are not easily suitable to increase it. A novel method developed at MSU is “virtual” welding, i.e. deformation of the cavity shape by applying systematically EBW on the cavity outer surface to induce controlled Nb material contraction in strategic positions. This technique allows to increase the cavity frequency with excellent precision and predictability, thus simplifying and making less expensive and more reliable HWR coarse tuning. Method and experimental results will be described and discussed.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY060
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THPF140	Unique Accelerator Integration Features of the Heavy Ion CW Driver Linac at FRIB	4051
	Y. Yamazaki, N.K. Bultman, A. Facco, M. Ikegami, F. Marti, G. Pozdeyev, J. Wei, Y. Zhang, Q. Zhao FRIB, East Lansing, Michigan, USA
	Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661 The FRIB driver linac is a front runner for the future high power hadron linacs, making a full use of CW, superconducting acceleration from very low β. Accelerator Driven Nuclear Waste Transmutation System (ADS), International Fusion Material Irradiation Facility (IFMIF), Project-X type proton accelerators for high energy physics and others may utilize the technologies developed for the design, construction, commissioning and power ramp up of the FRIB linac. Although each technology has been already well developed individually (except for charge stripper), their integration is another challenge. In addition, extremely high Bragg peak of uranium beams (several thousand times as high as that of proton beams) gives rise to one of the biggest challenges in many aspects. This report summarizes these challenges and their mitigations, emphasizing the commonly overlooked features.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF140
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Virtual Welding as a Tool for Superconducting Cavity Coarse Tuning

3412

A. Facco, C. Compton, J. Popielarski, G.J. Velianoff
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
Reaching the final frequency in the construction of Superconducting Half-Wave Resonators (HWR), either coaxial or spoke, is often a painful and time consuming process which requires several intermediate frequency tests and parts machining between subsequent welding steps. In spite of that, the final frequency error after final welding is often far from the target due to difficult to predict material contraction and cavity deformation induced by electron beam welding (EBW). Final coarse tuning is required by plastic deformation or differential etching. In coaxial HWR, both can decrease the cavity frequency but are not easily suitable to increase it. A novel method developed at MSU is “virtual” welding, i.e. deformation of the cavity shape by applying systematically EBW on the cavity outer surface to induce controlled Nb material contraction in strategic positions. This technique allows to increase the cavity frequency with excellent precision and predictability, thus simplifying and making less expensive and more reliable HWR coarse tuning. Method and experimental results will be described and discussed.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPTY060

Export •

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

THPF140

Unique Accelerator Integration Features of the Heavy Ion CW Driver Linac at FRIB

4051

Y. Yamazaki, N.K. Bultman, A. Facco, M. Ikegami, F. Marti, G. Pozdeyev, J. Wei, Y. Zhang, Q. Zhao
FRIB, East Lansing, Michigan, USA

Funding: Work supported by the U.S. Department of Energy Office of Science under Cooperative Agreement DE-SC0000661
The FRIB driver linac is a front runner for the future high power hadron linacs, making a full use of CW, superconducting acceleration from very low β. Accelerator Driven Nuclear Waste Transmutation System (ADS), International Fusion Material Irradiation Facility (IFMIF), Project-X type proton accelerators for high energy physics and others may utilize the technologies developed for the design, construction, commissioning and power ramp up of the FRIB linac. Although each technology has been already well developed individually (except for charge stripper), their integration is another challenge. In addition, extremely high Bragg peak of uranium beams (several thousand times as high as that of proton beams) gives rise to one of the biggest challenges in many aspects. This report summarizes these challenges and their mitigations, emphasizing the commonly overlooked features.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-THPF140

Export •

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