SRF2021 - List of Keywords (klystron)

Paper	Title	Other Keywords	Page
WEPFAV006	ILC Energy Upgrade Paths to 3 TeV	cavity, linac, SRF, cryomodule	549
	H. Padamsee Fermilab, Batavia, Illinois, USA
	We consider ILC upgrade paths beyond 1 TeV: (1) to 2 TeV and (2) to 3 TeV depending on the needs of high energy physics. Parameters for four scenarios will be presented and challenges discussed. 1. From 1 TeV to 2 TeV based on: a. Gradient advances of Nb cavities to 55 MV/m anticipated from on-going SRF R&D on Nb structures discussed in Section 4.3.x. b. Radically new travelling wave (TW) superconducting structures [1,2] optimized for effective gradients of 70+ MV/m, along with 100% increase in R/Q (discussed in more detail in Section 4.3.x). The large gain in R/Q has a major beneficial impact on the refrigerator heat load, the RF power, and the AC operating power. OR 2. From 1 TeV to 3 TeV based on a. Radically new travelling wave (TW) superconducting structures [1,2] optimized for effective gradients of 70+ MV/m, along with 100% increase in R/Q. The large gain in R/Q has a major beneficial impact on heat load, RF power, and the AC operating power. b. 80 MV/m gradient potential for Nb₃Sn [3] with Q of 1x10¹⁰, based on extrapolations from high power pulsed measurements on single cell Nb₃Sn cavities. Further, the operating temperature is 4.2 K instead of 2K.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPFAV006
About •	Received ※ 13 June 2021 — Accepted ※ 29 September 2021 — Issue date ※ 16 May 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

THPFDV008	Research on Ceramic for RF Window	electron, multipactoring, cavity, Windows	771
	Y. Yamamoto, K. Nakamura, H. Yoshizumi Kyocera Corporation, Corporate Fine Ceramics Group, Kyoto, Japan S. Michizono, Y. Yamamoto KEK, Ibaraki, Japan
	Kyocera and KEK had started joint research on developing materials that satisfy the required characteristics as RF window materials. In previous studies, AO479B was developed, and it has been applied to some products. However, AO479B has size limitation in applying to products. Recently, large RF windows is demanded. Therefore, we have developed a new material AO479U which is designed to be applied to products regardless of the product size. In this report, the characteristics of AO479U was evaluated by comparing it with other materials, including the presence or absence of TiN coating. In order to clarify how the differences of materials or manufacturing processes contributes to heat generation and multipactor discharge occurring in RF windows, we measured important characteristics as RF window materials (relative permittivity, dielectric loss tangent, surface resistance, volume resistivity, secondary electron emission coefficient, and TiN thickness), and investigated the relationships of them and materials or manufacturing processes.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPFDV008
About •	Received ※ 18 June 2021 — Revised ※ 06 December 2021 — Accepted ※ 28 February 2022 — Issue date ※ 01 May 2022
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

WEPFAV006

ILC Energy Upgrade Paths to 3 TeV

cavity, linac, SRF, cryomodule

549

H. Padamsee
Fermilab, Batavia, Illinois, USA

We consider ILC upgrade paths beyond 1 TeV: (1) to 2 TeV and (2) to 3 TeV depending on the needs of high energy physics. Parameters for four scenarios will be presented and challenges discussed. 1. From 1 TeV to 2 TeV based on: a. Gradient advances of Nb cavities to 55 MV/m anticipated from on-going SRF R&D on Nb structures discussed in Section 4.3.x. b. Radically new travelling wave (TW) superconducting structures [1,2] optimized for effective gradients of 70+ MV/m, along with 100% increase in R/Q (discussed in more detail in Section 4.3.x). The large gain in R/Q has a major beneficial impact on the refrigerator heat load, the RF power, and the AC operating power. OR 2. From 1 TeV to 3 TeV based on a. Radically new travelling wave (TW) superconducting structures [1,2] optimized for effective gradients of 70+ MV/m, along with 100% increase in R/Q. The large gain in R/Q has a major beneficial impact on heat load, RF power, and the AC operating power. b. 80 MV/m gradient potential for Nb₃Sn [3] with Q of 1x10¹⁰, based on extrapolations from high power pulsed measurements on single cell Nb₃Sn cavities. Further, the operating temperature is 4.2 K instead of 2K.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-WEPFAV006

About •

Received ※ 13 June 2021 — Accepted ※ 29 September 2021 — Issue date ※ 16 May 2022

Cite •

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

THPFDV008

Research on Ceramic for RF Window

electron, multipactoring, cavity, Windows

771

Y. Yamamoto, K. Nakamura, H. Yoshizumi
Kyocera Corporation, Corporate Fine Ceramics Group, Kyoto, Japan
S. Michizono, Y. Yamamoto
KEK, Ibaraki, Japan

Kyocera and KEK had started joint research on developing materials that satisfy the required characteristics as RF window materials. In previous studies, AO479B was developed, and it has been applied to some products. However, AO479B has size limitation in applying to products. Recently, large RF windows is demanded. Therefore, we have developed a new material AO479U which is designed to be applied to products regardless of the product size. In this report, the characteristics of AO479U was evaluated by comparing it with other materials, including the presence or absence of TiN coating. In order to clarify how the differences of materials or manufacturing processes contributes to heat generation and multipactor discharge occurring in RF windows, we measured important characteristics as RF window materials (relative permittivity, dielectric loss tangent, surface resistance, volume resistivity, secondary electron emission coefficient, and TiN thickness), and investigated the relationships of them and materials or manufacturing processes.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2021-THPFDV008

About •

Received ※ 18 June 2021 — Revised ※ 06 December 2021 — Accepted ※ 28 February 2022 — Issue date ※ 01 May 2022

Cite •

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