IPAC2015 - List of Authors (Gurran, L.)

Paper	Title	Page
WEPHA052	Test Cavity and Cryostat for SRF Thin Film Evaluation	3232
	O.B. Malyshev, P. Goudket, L. Gurran, D.O. Malyshev, S.M. Pattalwar, R. Valizadeh STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom G. Burt, L. Gurran Cockcroft Institute, Lancaster University, Lancaster, United Kingdom P. Goudket, O.B. Malyshev, S.M. Pattalwar, R. Valizadeh Cockcroft Institute, Warrington, Cheshire, United Kingdom T.J. Jones, E.S. Jordan STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom
	In developing superconducting coatings for SRF cavities, the coated samples are tested using various techniques such as resistance measurements, AC and DC magnetometry which provide information about the superconducting properties of the films such as RRR, Hc1, Hc2 and vortex dynamics. However, these results do not allow the prediction of the superconducting properties at RF frequencies. A dedicated RF cavity was designed to evaluate surface resistive losses on a flat sample. The cavity contains two parts: a half-elliptical cell made of bulk Nb and a flat Nb disc. The two parts can be thermally and electrically isolated via a vacuum gap, whereas the electromagnetic fields are constrained through the use of RF chokes. Both parts are conduction cooled hence the system is cryogen free. The flat disk can be replaced with a sample, such as a Cu disc coated with Nb film. The RF test provide the cavity Q-factor and thermometrical measurements of the losses on the sample. The design advantages are that the sample disc can be easily installed and replaced; installing a new sample requires no brazing/welding/vacuum or RF seal, so the sample preparation is simple and inexpensive.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPHA052
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WEPHA053	Surface Resistance RF Measurements of Materials Used for Accelerator Vacuum Chambers	3235
	P. Goudket, L. Gurran, O.B. Malyshev, M.D. Roper, R. Valizadeh, S. Wilde STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom G. Burt, L. Gurran Cockcroft Institute, Lancaster University, Lancaster, United Kingdom P. Goudket, O.B. Malyshev, R. Valizadeh Cockcroft Institute, Warrington, Cheshire, United Kingdom S. Wilde Loughborough University, Loughborough, Leicestershire, United Kingdom
	The RF surface resistance of accelerator vacuum chamber walls can have a significant impact on the beam quality. There is a need to know how the use of a new material, surface coating or surface treatment can affect the RF surface resistance. ASTeC and Lancaster University have designed and built two test cavities where one face can be replaced with a sample in the form of a flat plate. The measurements are performed with a network analyser at the resonant frequency of approximately 7.8 GHz.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPHA053
Export •	reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)

Paper

Title

Page

Test Cavity and Cryostat for SRF Thin Film Evaluation

3232

O.B. Malyshev, P. Goudket, L. Gurran, D.O. Malyshev, S.M. Pattalwar, R. Valizadeh
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
G. Burt, L. Gurran
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
P. Goudket, O.B. Malyshev, S.M. Pattalwar, R. Valizadeh
Cockcroft Institute, Warrington, Cheshire, United Kingdom
T.J. Jones, E.S. Jordan
STFC/DL, Daresbury, Warrington, Cheshire, United Kingdom

In developing superconducting coatings for SRF cavities, the coated samples are tested using various techniques such as resistance measurements, AC and DC magnetometry which provide information about the superconducting properties of the films such as RRR, Hc1, Hc2 and vortex dynamics. However, these results do not allow the prediction of the superconducting properties at RF frequencies. A dedicated RF cavity was designed to evaluate surface resistive losses on a flat sample. The cavity contains two parts: a half-elliptical cell made of bulk Nb and a flat Nb disc. The two parts can be thermally and electrically isolated via a vacuum gap, whereas the electromagnetic fields are constrained through the use of RF chokes. Both parts are conduction cooled hence the system is cryogen free. The flat disk can be replaced with a sample, such as a Cu disc coated with Nb film. The RF test provide the cavity Q-factor and thermometrical measurements of the losses on the sample. The design advantages are that the sample disc can be easily installed and replaced; installing a new sample requires no brazing/welding/vacuum or RF seal, so the sample preparation is simple and inexpensive.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPHA052

Export •

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

WEPHA053

Surface Resistance RF Measurements of Materials Used for Accelerator Vacuum Chambers

3235

P. Goudket, L. Gurran, O.B. Malyshev, M.D. Roper, R. Valizadeh, S. Wilde
STFC/DL/ASTeC, Daresbury, Warrington, Cheshire, United Kingdom
G. Burt, L. Gurran
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
P. Goudket, O.B. Malyshev, R. Valizadeh
Cockcroft Institute, Warrington, Cheshire, United Kingdom
S. Wilde
Loughborough University, Loughborough, Leicestershire, United Kingdom

The RF surface resistance of accelerator vacuum chamber walls can have a significant impact on the beam quality. There is a need to know how the use of a new material, surface coating or surface treatment can affect the RF surface resistance. ASTeC and Lancaster University have designed and built two test cavities where one face can be replaced with a sample in the form of a flat plate. The measurements are performed with a network analyser at the resonant frequency of approximately 7.8 GHz.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2015-WEPHA053

Export •

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