SRF2021 - List of Authors (Takahashi, K.)

Paper	Title	Page
SUPCAV008	Design and Construction of Nb₃Sn Vapor Diffusion Coating System at KEK	23
	K. Takahashi, T. Okada Sokendai, Ibaraki, Japan H. Ito, E. Kako, T. Konomi, H. Sakai, K. Umemori KEK, Ibaraki, Japan
	Vapor diffusion Nb₃Sn coating system was developed at KEK. At most 1.3GHz 3-cell cavity can be coat with the coating system. The coating system consists of a coating chamber made of Nb, a vacuum furnace for heating the Nb chamber, and a heating device of Tin in the crucible. The Nb chamber vacuum and the furnace vacuum are isolated to prevent contamination from the furnace. There is a heating device for increasing Tin vapor pressure. In this presentation, the design and construction of the coating system are reported.
	Poster SUPCAV008 [0.986 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPCAV008
About •	Received ※ 21 June 2021 — Accepted ※ 18 November 2021 — Issue date ※ 11 April 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

SUPCAV009	First Nb₃Sn Coating and Cavity Performance Result at KEK	27
	K. Takahashi, T. Okada Sokendai, Ibaraki, Japan H. Ito, E. Kako, T. Konomi, H. Sakai, K. Umemori KEK, Ibaraki, Japan
	At KEK, Nb₃Sn vapor diffusion R&D for High-Q has just started. We have performed Nb₃Sn coating on niobium samples and characterized these samples. We optimized the cavity coating parameter from the result of characterized samples. After optimizing the parameter, we have performed Nb₃Sn coating on a TESLA-like single-cell Nb cavity and measured cavity performance in vertical tests. This presentation presents the result of the cavity coating and performance results.
	Poster SUPCAV009 [1.481 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPCAV009
About •	Received ※ 21 June 2021 — Accepted ※ 18 March 2022 — Issue date ※ 16 May 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FROFDV01	Systematic Investigation of Mid-T Furnace Baking for High-Q Performance	881
	H. Ito, A. Araki, K. Umemori KEK, Ibaraki, Japan K. Takahashi Sokendai, Ibaraki, Japan
	We report on an investigation of the effect of a new baking process called "furnace baking" on the quality factor. Furnace baking is performed as the final step of the cavity surface treatment; the cavities are heated in a vacuum furnace in a temperature range of 200-800C for 3 h, followed by high-pressure rinsing and radio-frequency measurement. We find the anti-Q-slope for cavities furnace-baked at a temperature range of 250 to 400C and a reduction in the residual resistance for all cavities. In particular, an extremely high Q value of 5·10¹⁰ at 16 MV/m and 2.0 K is obtained for cavities furnace-baked at 300C.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-FROFDV01
About •	Received ※ 21 June 2021 — Accepted ※ 24 February 2022 — Issue date ※ 30 April 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Design and Construction of Nb₃Sn Vapor Diffusion Coating System at KEK

23

K. Takahashi, T. Okada
Sokendai, Ibaraki, Japan
H. Ito, E. Kako, T. Konomi, H. Sakai, K. Umemori
KEK, Ibaraki, Japan

Vapor diffusion Nb₃Sn coating system was developed at KEK. At most 1.3GHz 3-cell cavity can be coat with the coating system. The coating system consists of a coating chamber made of Nb, a vacuum furnace for heating the Nb chamber, and a heating device of Tin in the crucible. The Nb chamber vacuum and the furnace vacuum are isolated to prevent contamination from the furnace. There is a heating device for increasing Tin vapor pressure. In this presentation, the design and construction of the coating system are reported.

Poster SUPCAV008 [0.986 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPCAV008

About •

Received ※ 21 June 2021 — Accepted ※ 18 November 2021 — Issue date ※ 11 April 2022

Cite •

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

SUPCAV009

First Nb₃Sn Coating and Cavity Performance Result at KEK

27

K. Takahashi, T. Okada
Sokendai, Ibaraki, Japan
H. Ito, E. Kako, T. Konomi, H. Sakai, K. Umemori
KEK, Ibaraki, Japan

At KEK, Nb₃Sn vapor diffusion R&D for High-Q has just started. We have performed Nb₃Sn coating on niobium samples and characterized these samples. We optimized the cavity coating parameter from the result of characterized samples. After optimizing the parameter, we have performed Nb₃Sn coating on a TESLA-like single-cell Nb cavity and measured cavity performance in vertical tests. This presentation presents the result of the cavity coating and performance results.

Poster SUPCAV009 [1.481 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-SUPCAV009

About •

Received ※ 21 June 2021 — Accepted ※ 18 March 2022 — Issue date ※ 16 May 2022

Cite •

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

FROFDV01

Systematic Investigation of Mid-T Furnace Baking for High-Q Performance

881

H. Ito, A. Araki, K. Umemori
KEK, Ibaraki, Japan
K. Takahashi
Sokendai, Ibaraki, Japan

We report on an investigation of the effect of a new baking process called "furnace baking" on the quality factor. Furnace baking is performed as the final step of the cavity surface treatment; the cavities are heated in a vacuum furnace in a temperature range of 200-800C for 3 h, followed by high-pressure rinsing and radio-frequency measurement. We find the anti-Q-slope for cavities furnace-baked at a temperature range of 250 to 400C and a reduction in the residual resistance for all cavities. In particular, an extremely high Q value of 5·10¹⁰ at 16 MV/m and 2.0 K is obtained for cavities furnace-baked at 300C.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-FROFDV01

About •

Received ※ 21 June 2021 — Accepted ※ 24 February 2022 — Issue date ※ 30 April 2022

Cite •

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