SRF2023 - List of Authors (Baudrier, M.)

Paper	Title	Page
TUPTB035	Design, Fabrication, and Test of a 175 MHz, β = 0.18, Half Wave Resonator for the IFMIF-DONES SRF-Linac	477
	J. Plouin, M. Baudrier, S. Chel, G. Devanz, A. Madur, L. Maurice, C. Servouin CEA-DRF-IRFU, France N. Bazin, G. Jullien CEA-IRFU, Gif-sur-Yvette, France
	The IFMIF-DONES facility will serve as a fusion-like neutron source for the assessment of materials damage in future fusion reactors. The neutron flux will be generated by the interaction between the lithium curtain and the deuteron beam from an RF linear accelerator at 40 MeV and nominal CW current of 125 mA. The last accelerating stage is a superconducting (SRF) Linac hosting five cryomodules. This SRF-Linac is equipped of two types of 175 MHz half wave superconducting cavities (HWRs). The first type of cavities (cryomodules 1 and 2), characterized by beta equal to 0.11, have been studied and qualified in the frame of IFMIF/EVEDA project. The development of the second type of cavities (cryomodules 3, 4 and 5), with higher beta of 0.18 is presented in this paper. A prototype has been designed, fabricated and tested in a vertical cryostat at CEA. The measured quality factor at nominal accelerating field (4.5 MV/m) is 2.3 10⁹ and keeps higher than 109 up to 10 MV/m, which gives confidence in the cavity design and preparation to reach the expected performances after integration in the SRF linac.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB035
About •	Received ※ 20 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 29 June 2023 — Issue date ※ 15 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRIBA02	Instrumentation for High Performance Cavities and Cryomodule Field Emission Analysis	978
	G. Devanz CEA-IRFU, Gif-sur-Yvette, France M. Baudrier, E. Cenni, L. Maurice, O. Piquet CEA-DRF-IRFU, France
	Field emission (FE) is one of the main reasons for the degradation of accelerator cryomodules, as field emitted current tends to become more severe during the beam operation. It is essential to better understand how this phenomenon is generated and evolves from the SRF cavity preparation in the clean room, through their assembly in the cryomodule until their final test and operation. Due to the shielding environment of a cavity in its vertical test stand, or the architecture of a cryomodule, the more faint radiation occurring at the FE onset remains undetected. More precise diagnostic and analysis tools are required to gain more information. We present the developpement of dedicated time-resolved detectors for the FE radiation which aim at improving its coverage in terms of solid angle and lower energy threshold sensitivity. We approach this topic through detailed simulation based on the Geant4 toolkit in order to analyse the interaction of FE radiation with the cavity environement and optimize the detectors with respect to their application in cryomodule or vertical test stands. We illustrate by analysing recent cryomodule experimental test data.
	Slides FRIBA02 [9.606 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-FRIBA02
About •	Received ※ 27 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 05 July 2023 — Issue date ※ 09 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

WEIBA01	Surface Engineering by ALD for Superconducting RF Cavities	615
	Y. Kalboussi, C.Z. Antoine, M. Baudrier, Q. Bertrand, C. Boulch, B. Delatte, G. Jullien, L. Maurice, Th. Proslier, P. Sahuquet, T.V. Vacher CEA-IRFU, Gif-sur-Yvette, France M. Asaduzzaman, T. Junginger UVIC, Victoria, Canada M. Asaduzzaman TRIUMF, Vancouver, Canada D. Dragoe ICMMO, Orsay, France F. Éozénou CEA-DRF-IRFU, France N. Lochet CEA, DES, Université Paris-Saclay, Gif-sur-Yvette, France D. Longuevergne, T. Pépin-Donat Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France F. Miserque CEA, LECA, Université Paris-Saclay, Gif-sur-Yvette, France
	Atomic Layer Deposition is a synthesis method that enable a unique control of thin films chemical composition and thickness over complex shape objects such as SRF cavities. This level of control opens the way to new surface treatments and to study their effect on RF cavity performances. We will present coupon and, in some cases, preliminary cavity results, from various surface engineering routes based on the deposition of thin oxides and nitrides films combined with post annealing treatments and study their interactions with the niobium. Three main research directions will be presented: 1/ replacing the niobium oxides by other surface layers (Al₂O₃, Y2O3, MgO) and probe their effect on the low and high field performances, 2/ doping with N and combine approaches 1/ and 2/ and finally 3/ optimize the superconducting properties of NbTiN multilayers on Nb and Sapphire.
	Slides WEIBA01 [13.613 MB]
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEIBA01
About •	Received ※ 06 July 2023 — Revised ※ 12 August 2023 — Accepted ※ 19 August 2023 — Issue date ※ 19 August 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Design, Fabrication, and Test of a 175 MHz, β = 0.18, Half Wave Resonator for the IFMIF-DONES SRF-Linac

477

J. Plouin, M. Baudrier, S. Chel, G. Devanz, A. Madur, L. Maurice, C. Servouin
CEA-DRF-IRFU, France
N. Bazin, G. Jullien
CEA-IRFU, Gif-sur-Yvette, France

The IFMIF-DONES facility will serve as a fusion-like neutron source for the assessment of materials damage in future fusion reactors. The neutron flux will be generated by the interaction between the lithium curtain and the deuteron beam from an RF linear accelerator at 40 MeV and nominal CW current of 125 mA. The last accelerating stage is a superconducting (SRF) Linac hosting five cryomodules. This SRF-Linac is equipped of two types of 175 MHz half wave superconducting cavities (HWRs). The first type of cavities (cryomodules 1 and 2), characterized by beta equal to 0.11, have been studied and qualified in the frame of IFMIF/EVEDA project. The development of the second type of cavities (cryomodules 3, 4 and 5), with higher beta of 0.18 is presented in this paper. A prototype has been designed, fabricated and tested in a vertical cryostat at CEA. The measured quality factor at nominal accelerating field (4.5 MV/m) is 2.3 10⁹ and keeps higher than 109 up to 10 MV/m, which gives confidence in the cavity design and preparation to reach the expected performances after integration in the SRF linac.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB035

About •

Received ※ 20 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 29 June 2023 — Issue date ※ 15 July 2023

Cite •

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

FRIBA02

Instrumentation for High Performance Cavities and Cryomodule Field Emission Analysis

978

G. Devanz
CEA-IRFU, Gif-sur-Yvette, France
M. Baudrier, E. Cenni, L. Maurice, O. Piquet
CEA-DRF-IRFU, France

Field emission (FE) is one of the main reasons for the degradation of accelerator cryomodules, as field emitted current tends to become more severe during the beam operation. It is essential to better understand how this phenomenon is generated and evolves from the SRF cavity preparation in the clean room, through their assembly in the cryomodule until their final test and operation. Due to the shielding environment of a cavity in its vertical test stand, or the architecture of a cryomodule, the more faint radiation occurring at the FE onset remains undetected. More precise diagnostic and analysis tools are required to gain more information. We present the developpement of dedicated time-resolved detectors for the FE radiation which aim at improving its coverage in terms of solid angle and lower energy threshold sensitivity. We approach this topic through detailed simulation based on the Geant4 toolkit in order to analyse the interaction of FE radiation with the cavity environement and optimize the detectors with respect to their application in cryomodule or vertical test stands. We illustrate by analysing recent cryomodule experimental test data.

Slides FRIBA02 [9.606 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-FRIBA02

About •

Received ※ 27 June 2023 — Revised ※ 28 June 2023 — Accepted ※ 05 July 2023 — Issue date ※ 09 July 2023

Cite •

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

WEIBA01

Surface Engineering by ALD for Superconducting RF Cavities

615

Y. Kalboussi, C.Z. Antoine, M. Baudrier, Q. Bertrand, C. Boulch, B. Delatte, G. Jullien, L. Maurice, Th. Proslier, P. Sahuquet, T.V. Vacher
CEA-IRFU, Gif-sur-Yvette, France
M. Asaduzzaman, T. Junginger
UVIC, Victoria, Canada
M. Asaduzzaman
TRIUMF, Vancouver, Canada
D. Dragoe
ICMMO, Orsay, France
F. Éozénou
CEA-DRF-IRFU, France
N. Lochet
CEA, DES, Université Paris-Saclay, Gif-sur-Yvette, France
D. Longuevergne, T. Pépin-Donat
Université Paris-Saclay, CNRS/IN2P3, IJCLab, Orsay, France
F. Miserque
CEA, LECA, Université Paris-Saclay, Gif-sur-Yvette, France

Atomic Layer Deposition is a synthesis method that enable a unique control of thin films chemical composition and thickness over complex shape objects such as SRF cavities. This level of control opens the way to new surface treatments and to study their effect on RF cavity performances. We will present coupon and, in some cases, preliminary cavity results, from various surface engineering routes based on the deposition of thin oxides and nitrides films combined with post annealing treatments and study their interactions with the niobium. Three main research directions will be presented: 1/ replacing the niobium oxides by other surface layers (Al₂O₃, Y2O3, MgO) and probe their effect on the low and high field performances, 2/ doping with N and combine approaches 1/ and 2/ and finally 3/ optimize the superconducting properties of NbTiN multilayers on Nb and Sapphire.

Slides WEIBA01 [13.613 MB]

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEIBA01

About •

Received ※ 06 July 2023 — Revised ※ 12 August 2023 — Accepted ※ 19 August 2023 — Issue date ※ 19 August 2023

Cite •

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