SRF2023 - List of Authors (Geng, R.L.)

Paper	Title	Page
WEPWB055	First Experience with Liquid Nitrogen Cleaning	706
	R.J.M.Y. Ruber, A.B. Eslinger, R.L. Geng JLab, Newport News, Virginia, USA
	Field emission caused by microscopic particulate contamination is a limiting factor for the performance of superconducting RF (SRF) cavities. In an SRF accelerator, particulates may be transported over the surface of an operational SRF cavity, becoming field emitters and consequentially degrading the performance of the SRF cavity. The most commonly used method for removing particulates from cavity surfaces is high-pressure ultra-pure water rinsing. We are developing a novel high-pressure liquid nitrogen cleaning technique that may possibly enable superior cleaning power and particulate removal from cavities in a cryomodule without taking apart the cryomodule components. This technique provides cleaning mechanisms beyond what are accessible by its high-pressure water counterpart and leaves no residues on the cleaned surface. We present the test setup and first experience.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB055
About •	Received ※ 15 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 27 June 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

MOPMB070	Development of a Non-Intrusive Leak Detection Method for SRF Linacs	275
	P. Pizzol, R.L. Geng ORNL, Oak Ridge, Tennessee, USA R. Afanador, J.D. Mammosser, V.S. Morozov, D.M. Vandygriff ORNL RAD, Oak Ridge, Tennessee, USA
	The SNS accelerator has been vital in delivering high-impact research for the world scientific community since 2006, with an availability of 99%. This high availability rate is crucial to the success of the facility, and after 16 years of operations, the aging of the components could start to impact this parameter. To mitigate this, condi-tion-based maintenance can be applied to areas of the LINAC to reduce or nullify the possibility of unwanted events that may damage the accelerator functionality. In this work, we describe the development of a non-intrusive leak detection methodology that verifies the health condition of the cryomodule isolation gate valve seals. In case of a sudden vacuum leak in a warm section between the cryomodules, these valves act as a final line of defense to protect the SRF cavities from atmosphere gases contamination, hence knowing their sealing integ-rity condition is paramount. Data taken from the ma-chine during different maintenance periods will be pre-sented, together with the analysis done, to verify the robustness of the numerical method vs. the experimental findings.
DOI •	reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB070
About •	Received ※ 16 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 02 July 2023
Cite •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

First Experience with Liquid Nitrogen Cleaning

706

R.J.M.Y. Ruber, A.B. Eslinger, R.L. Geng
JLab, Newport News, Virginia, USA

Field emission caused by microscopic particulate contamination is a limiting factor for the performance of superconducting RF (SRF) cavities. In an SRF accelerator, particulates may be transported over the surface of an operational SRF cavity, becoming field emitters and consequentially degrading the performance of the SRF cavity. The most commonly used method for removing particulates from cavity surfaces is high-pressure ultra-pure water rinsing. We are developing a novel high-pressure liquid nitrogen cleaning technique that may possibly enable superior cleaning power and particulate removal from cavities in a cryomodule without taking apart the cryomodule components. This technique provides cleaning mechanisms beyond what are accessible by its high-pressure water counterpart and leaves no residues on the cleaned surface. We present the test setup and first experience.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-WEPWB055

About •

Received ※ 15 June 2023 — Revised ※ 24 June 2023 — Accepted ※ 26 June 2023 — Issue date ※ 27 June 2023

Cite •

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

MOPMB070

Development of a Non-Intrusive Leak Detection Method for SRF Linacs

275

P. Pizzol, R.L. Geng
ORNL, Oak Ridge, Tennessee, USA
R. Afanador, J.D. Mammosser, V.S. Morozov, D.M. Vandygriff
ORNL RAD, Oak Ridge, Tennessee, USA

The SNS accelerator has been vital in delivering high-impact research for the world scientific community since 2006, with an availability of 99%. This high availability rate is crucial to the success of the facility, and after 16 years of operations, the aging of the components could start to impact this parameter. To mitigate this, condi-tion-based maintenance can be applied to areas of the LINAC to reduce or nullify the possibility of unwanted events that may damage the accelerator functionality. In this work, we describe the development of a non-intrusive leak detection methodology that verifies the health condition of the cryomodule isolation gate valve seals. In case of a sudden vacuum leak in a warm section between the cryomodules, these valves act as a final line of defense to protect the SRF cavities from atmosphere gases contamination, hence knowing their sealing integ-rity condition is paramount. Data taken from the ma-chine during different maintenance periods will be pre-sented, together with the analysis done, to verify the robustness of the numerical method vs. the experimental findings.

DOI •

reference for this paper ※ doi:10.18429/JACoW-SRF2023-MOPMB070

About •

Received ※ 16 June 2023 — Revised ※ 27 June 2023 — Accepted ※ 28 June 2023 — Issue date ※ 02 July 2023

Cite •

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