SRF2023 - List of Authors (Bice, D.J.)

Paper	Title	Page
TUPTB041	Visual, Optical and Replica Inspections: Surface Preparation of 650 MHz Nb Cavity for PIP-II Linac	507
	V. Chouhan, D.J. Bice, D.A. Burk, M.K. Ng, G. Wu Fermilab, Batavia, Illinois, USA
	Surface preparation of niobium superconducting RF cavities is a critical step for achieving good RF performance under the superconducting state. Surface defect, roughness, and contamination affect the accelerating gradient and quality factor of the cavities. We report surface inspection methods used to control the surface processing of 650 MHz cavities that will be used in the pre-production cryomodule for PIP-II linac. The cavity surface was routinely inspected visually, with an optical camera, and by microscopic scanning of surface replicas. This article covers details on the surface inspection methods and surface polishing process used to repair the surface.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB041
About •	Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 12 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPTB042	Latest Development of Electropolishing Optimization for 650 MHz Cavity	512
	V. Chouhan, D.J. Bice, D.A. Burk, S.K. Chandrasekaran, A.T. Cravatta, P.F. Dubiel, G.V. Eremeev, F. Furuta, O.S. Melnychuk, A.V. Netepenko, M.K. Ng, J.P. Ozelis, H. Park, T.J. Ring, G. Wu Fermilab, Batavia, Illinois, USA B.M. Guilfoyle, M.P. Kelly, T. Reid ANL, Lemont, Illinois, USA
	Electropolishing (EP) of 1.3 GHz niobium (Nb) superconducting RF cavities is conducted to achieve a desired smooth and contaminant-free surface that yields good RF performance. Achieving a smooth surface of a large-sized elliptical cavity with the standard EP conditions was found to be challenging. This work aimed to conduct a systematic parametric EP study to understand the effects of various EP parameters on the surface of 650 MHz cavities used in PIP-II linac. Parameters optimized in this study provided a smooth surface of the cavities. The electropolished cavities met the baseline requirement of field gradient and qualified for further surface treatment to improve the cavity quality factor.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB042
About •	Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 06 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPTB047	The Evaluation of Mechanical Properties of LB650 Cavities	536
	G. Wu, S.D. Adams, D.J. Bice, S.K. Chandrasekaran, I.V. Gonin, C.J. Grimm, J.P. Holzbauer, T.N. Khabiboulline, C.S. Narug, J.P. Ozelis, H. Park, G.V. Romanov, R. Thiede, R. Treece, A.D. Wixson Fermilab, Batavia, Illinois, USA K.E. McGee FRIB, East Lansing, Michigan, USA
	Funding: This manuscript has been authored by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics. The 650 MHz cavities have a stronger requirement of niobium mechanical properties because of the geometric shape of the cavity due to reduced beta. The mechanical property of the niobium half-cell was measured following various heat treatments. The 5-cell cavities were tested in a controlled drop test fashion and the real-world road test. The result showed that the 900C heat treatment was compatible with cavity handling and transportation during production. The test provides the bases of the transportation specification and shipping container design guidelines.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB047
About •	Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 14 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

FRIBA01	SRF R&D for FRIB Linac Energy Upgrade with High-performance Medium-beta Elliptical Cavity CW Cryomodules
	S.H. Kim, W. Chang, K. Elliott, W. Hartung, K.E. McGee, E.S. Metzgar, P.N. Ostroumov, L. Popielarski, J. Rathke, T. Xu, S. Zhao FRIB, East Lansing, Michigan, USA D.J. Bice, C. Contreras-Martinez, G.V. Eremeev, Y.M. Pischalnikov Fermilab, Batavia, Illinois, USA B.M. Guilfoyle, M.P. Kelly, T. Reid ANL, Lemont, Illinois, USA
	Funding: Work supported by the U.S. Department of Energy under Award Number DE-SC0000661. Further support provided by the US Department of Energy under Cooperative Agreement award number DE-SC0018362. Michigan State University is pursuing SRF R&D for FRIB400 upgrade, doubling the FRIB linac beam energy (400 MeV/u for the heaviest uranium beam) using ßopt=0.65 644 MHz 5-cell elliptical cavities. We have achieved unprecedented Q₀ in this cavity class, Q₀ = 3.5·10¹⁰ at E_acc of 17.5 MV/m in a nitrogen-doped bare niobium cavity in collaboration with FNAL and ANL. The next missions are achieving such high Q₀ in jacketed cavities and in cryomodules, achieving field-emission free performance at Epeak of 40 MV/m with reproducibility, developing a compact two-window high-power fundamental power coupler (15 kW CW), and achieving stable resonance control of cavities integrated with tuners in cryomodules. In this talk, we will present progress of the SRF R&D and discuss future plan.
	Slides FRIBA01 [2.513 MB]
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Paper

Title

Page

Visual, Optical and Replica Inspections: Surface Preparation of 650 MHz Nb Cavity for PIP-II Linac

507

V. Chouhan, D.J. Bice, D.A. Burk, M.K. Ng, G. Wu
Fermilab, Batavia, Illinois, USA

Surface preparation of niobium superconducting RF cavities is a critical step for achieving good RF performance under the superconducting state. Surface defect, roughness, and contamination affect the accelerating gradient and quality factor of the cavities. We report surface inspection methods used to control the surface processing of 650 MHz cavities that will be used in the pre-production cryomodule for PIP-II linac. The cavity surface was routinely inspected visually, with an optical camera, and by microscopic scanning of surface replicas. This article covers details on the surface inspection methods and surface polishing process used to repair the surface.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB041

About •

Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 27 June 2023 — Issue date ※ 12 July 2023

Cite •

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

TUPTB042

Latest Development of Electropolishing Optimization for 650 MHz Cavity

512

V. Chouhan, D.J. Bice, D.A. Burk, S.K. Chandrasekaran, A.T. Cravatta, P.F. Dubiel, G.V. Eremeev, F. Furuta, O.S. Melnychuk, A.V. Netepenko, M.K. Ng, J.P. Ozelis, H. Park, T.J. Ring, G. Wu
Fermilab, Batavia, Illinois, USA
B.M. Guilfoyle, M.P. Kelly, T. Reid
ANL, Lemont, Illinois, USA

Electropolishing (EP) of 1.3 GHz niobium (Nb) superconducting RF cavities is conducted to achieve a desired smooth and contaminant-free surface that yields good RF performance. Achieving a smooth surface of a large-sized elliptical cavity with the standard EP conditions was found to be challenging. This work aimed to conduct a systematic parametric EP study to understand the effects of various EP parameters on the surface of 650 MHz cavities used in PIP-II linac. Parameters optimized in this study provided a smooth surface of the cavities. The electropolished cavities met the baseline requirement of field gradient and qualified for further surface treatment to improve the cavity quality factor.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB042

About •

Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 06 July 2023

Cite •

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

TUPTB047

The Evaluation of Mechanical Properties of LB650 Cavities

536

G. Wu, S.D. Adams, D.J. Bice, S.K. Chandrasekaran, I.V. Gonin, C.J. Grimm, J.P. Holzbauer, T.N. Khabiboulline, C.S. Narug, J.P. Ozelis, H. Park, G.V. Romanov, R. Thiede, R. Treece, A.D. Wixson
Fermilab, Batavia, Illinois, USA
K.E. McGee
FRIB, East Lansing, Michigan, USA

Funding: This manuscript has been authored by Fermi Research Alliance, LLC, under Contract No. DE-AC02-07CH11359 with the U.S. Department of Energy, Office of Science, Office of High Energy Physics.
The 650 MHz cavities have a stronger requirement of niobium mechanical properties because of the geometric shape of the cavity due to reduced beta. The mechanical property of the niobium half-cell was measured following various heat treatments. The 5-cell cavities were tested in a controlled drop test fashion and the real-world road test. The result showed that the 900C heat treatment was compatible with cavity handling and transportation during production. The test provides the bases of the transportation specification and shipping container design guidelines.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-TUPTB047

About •

Received ※ 19 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 14 July 2023

Cite •

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

FRIBA01

SRF R&D for FRIB Linac Energy Upgrade with High-performance Medium-beta Elliptical Cavity CW Cryomodules

S.H. Kim, W. Chang, K. Elliott, W. Hartung, K.E. McGee, E.S. Metzgar, P.N. Ostroumov, L. Popielarski, J. Rathke, T. Xu, S. Zhao
FRIB, East Lansing, Michigan, USA
D.J. Bice, C. Contreras-Martinez, G.V. Eremeev, Y.M. Pischalnikov
Fermilab, Batavia, Illinois, USA
B.M. Guilfoyle, M.P. Kelly, T. Reid
ANL, Lemont, Illinois, USA

Funding: Work supported by the U.S. Department of Energy under Award Number DE-SC0000661. Further support provided by the US Department of Energy under Cooperative Agreement award number DE-SC0018362.
Michigan State University is pursuing SRF R&D for FRIB400 upgrade, doubling the FRIB linac beam energy (400 MeV/u for the heaviest uranium beam) using ßopt=0.65 644 MHz 5-cell elliptical cavities. We have achieved unprecedented Q₀ in this cavity class, Q₀ = 3.5·10¹⁰ at E_acc of 17.5 MV/m in a nitrogen-doped bare niobium cavity in collaboration with FNAL and ANL. The next missions are achieving such high Q₀ in jacketed cavities and in cryomodules, achieving field-emission free performance at Epeak of 40 MV/m with reproducibility, developing a compact two-window high-power fundamental power coupler (15 kW CW), and achieving stable resonance control of cavities integrated with tuners in cryomodules. In this talk, we will present progress of the SRF R&D and discuss future plan.

Slides FRIBA01 [2.513 MB]

Cite •

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