SRF2017 - List of Keywords (software)

Paper	Title	Other Keywords	Page
TUPB069	Rigorous Data Processing and Automatic Documentation of SRF Cold Tests	ion, LabView, SRF, cavity	543
	K.G. Hernández-Chahín Universidad de Guanajuato, División de Ciencias e Ingenierías, León, Mexico S. Aull, P.F. Fernández López, K.G. Hernández-Chahín, N. Schwerg, N. Stapley CERN, Geneva, Switzerland
	Performance curves for SRF cavities are derived from primary quantities which are processed by software. Commonly, the mathematical implementation of this analysis is hidden in software such as Excel or LabVIEW, making it difficult to verify or to trace, while text-based programming like Python and MATLAB require some programming skills for review and use. As part of an initiative to consolidate and standardise SRF data analysis tools, we present a Python program converting a module containing the collection of all commonly used functions into a \LaTeX (PDF) document carrying all features of the implementation and allowing for a review by SRF experts, not programmers. The resulting document is the reference for non-experts, beginners and test stand operators. The module is imported in any subsequent processing and analysis steps like the symbolic analysis of the measurement uncertainties or the study of sensitivities. As an additional layer of protection the functions can be further wrapped including assertions, type and sanity checks. This process maximises function reuse, reduces the risk of human errors and guarantees automatically validated and documented cold test results.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB069
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

TUPB078	SUBU Characterisation: Bath Fluid Dynamics vs Etching Rate	ion, cavity, simulation, ISOL	575
	A. Perez Rodriguez, L.M.A. Ferreira, A. Sublet CERN, Geneva, Switzerland
	The chemical polishing bath SUBU is widely used at CERN to prepare copper RF cavities surfaces before niobium thin film coating; examples are HIE-ISOLDE, LHC and future FCC accelerating cavities. The performance of the polishing process is affected by bath temperature and fluid dynamics. As part of on-going activities to characterise SUBU, the actual study was done to identify a correlation between the etching rate and physical parameters linked to the bath fluid dynamics. A first approach was made using experimental data from a simplified model setup, transposing them via numerical simulation to a real cavity geometry and verifying the agreement with an experiment in a real size (HIE-ISOLDE) mock-up. In a second approach to improve the accuracy of the calculation, the relation of the measured local etching rates, extracted from the mock-up, to flow dynamics quantities extracted from simulation was investigated. As a result, a correlation between the local etching rate and the turbulence kinetic energy was obtained. This correlation can be exploited to improve the polishing tools and so optimise the current process, as well as to predict the etching rate in other cavity geometries.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB078
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Other Keywords

Page

TUPB069

Rigorous Data Processing and Automatic Documentation of SRF Cold Tests

ion, LabView, SRF, cavity

543

K.G. Hernández-Chahín
Universidad de Guanajuato, División de Ciencias e Ingenierías, León, Mexico
S. Aull, P.F. Fernández López, K.G. Hernández-Chahín, N. Schwerg, N. Stapley
CERN, Geneva, Switzerland

Performance curves for SRF cavities are derived from primary quantities which are processed by software. Commonly, the mathematical implementation of this analysis is hidden in software such as Excel or LabVIEW, making it difficult to verify or to trace, while text-based programming like Python and MATLAB require some programming skills for review and use. As part of an initiative to consolidate and standardise SRF data analysis tools, we present a Python program converting a module containing the collection of all commonly used functions into a \LaTeX (PDF) document carrying all features of the implementation and allowing for a review by SRF experts, not programmers. The resulting document is the reference for non-experts, beginners and test stand operators. The module is imported in any subsequent processing and analysis steps like the symbolic analysis of the measurement uncertainties or the study of sensitivities. As an additional layer of protection the functions can be further wrapped including assertions, type and sanity checks. This process maximises function reuse, reduces the risk of human errors and guarantees automatically validated and documented cold test results.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB069

Export •

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

TUPB078

SUBU Characterisation: Bath Fluid Dynamics vs Etching Rate

ion, cavity, simulation, ISOL

575

A. Perez Rodriguez, L.M.A. Ferreira, A. Sublet
CERN, Geneva, Switzerland

The chemical polishing bath SUBU is widely used at CERN to prepare copper RF cavities surfaces before niobium thin film coating; examples are HIE-ISOLDE, LHC and future FCC accelerating cavities. The performance of the polishing process is affected by bath temperature and fluid dynamics. As part of on-going activities to characterise SUBU, the actual study was done to identify a correlation between the etching rate and physical parameters linked to the bath fluid dynamics. A first approach was made using experimental data from a simplified model setup, transposing them via numerical simulation to a real cavity geometry and verifying the agreement with an experiment in a real size (HIE-ISOLDE) mock-up. In a second approach to improve the accuracy of the calculation, the relation of the measured local etching rates, extracted from the mock-up, to flow dynamics quantities extracted from simulation was investigated. As a result, a correlation between the local etching rate and the turbulence kinetic energy was obtained. This correlation can be exploited to improve the polishing tools and so optimise the current process, as well as to predict the etching rate in other cavity geometries.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-SRF2017-TUPB078

Export •

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