SRF2015 - List of Authors (Kiefl, R.)

Paper	Title	Page
MOPB050	Characterization of SRF Materials at the TRIUMF muSR Facility	205
	R.E. Laxdal, T.J. Buck, T. Junginger, P. Kolb, Y.Y. Ma, L. Yang, Z.Y. Yao TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada S.H. Abidi University of Toronto, Toronto, Ontario, Canada R. Kiefl UBC & TRIUMF, Vancouver, British Columbia, Canada
	MuSR is a powerful tool to probe local magnetism and hence can be used to diagnose flux penetration in Type-II superconductors. Samples produced at TRIUMF and with collaborators in both coin shaped and ellipsoidal geometries have been characterized by applying either transverse or parallel fields between 0 and 300mT and measuring flux entry as a function of applied field. Samples include Nb treated in standard ways including forming, chemistry, and heat treatments. Further, Nb samples have been doped with Nitrogen and coated with a 2 micron layer of Nb3Sn by collaborators from FNAL and Cornell respectively and measured in three field/geometry configurations. Analysis of the method in particular the effects of geometry and the role of pinning will be presented. Results of the measurements will be presented.
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MOPB051	Muon Spin Rotation on Treated Nb Samples in Parallel Field Geometry	210
	S. Gheidi UBC, Vancouver, B.C., Canada T.J. Buck, T. Junginger, R.E. Laxdal, G. Morris TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada M. Dehn TUM/Physik, Garching bei München, Germany R. Kiefl UBC & TRIUMF, Vancouver, British Columbia, Canada
	MuSR is a powerful tool to probe local magnetism and hence can be used to diagnose the entry of magnetic flux in superconductors. First measurements on SRF samples were done with an external DC field applied perpendicular to the sample1 (transverse geometry) with the muons applied to the sample face. Here the results are strongly impacted by demagnetization, pinning strength and edge effects. A new spectrometer has been developed to allow sample testing with a field varying from 0 to 300mT applied along the sample face (parallel geometry) analogous to rf fields in SRF resonators. The geometry is characterized by a small demagnetization factor reducing the impact of pinning and edge effects on field of first flux entry. The beamline installation and first results comparing transverse and parallel results will be presented. 1 Grassellino et al. Muon spin rotation studies of niobium for superconducting rf applications. Phys. Rev. ST Accel. Beams, 16:062002, Jun 2013.
	Poster MOPB051 [0.719 MB]
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TUPB041	Testing Nb3Sn Coating Using muSR	651
	R.E. Laxdal, T.J. Buck TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada S. Gheidi UBC, Vancouver, B.C., Canada R. Kiefl UBC & TRIUMF, Vancouver, British Columbia, Canada M. Liepe, S. Posen Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	The SRF group at TRIUMF has tested samples relevant for SRF application since 2010 using the TRIUMF μSR facility. In this study collaborators at Cornell coat a Nb coin and a Nb ellipsoid sample with Nb3Sn for characterization using μSR at TRIUMF. Field of first flux entry measurements are performed at M20 on both samples. Measurements include the vortex nucleation field Hnucleate and Tc of both Nb3Sn and Nb. Interestingly the Nb3Sn increases the vortex nucleation field at 2K over standard Nb samples.
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Paper

Title

Page

Characterization of SRF Materials at the TRIUMF muSR Facility

205

R.E. Laxdal, T.J. Buck, T. Junginger, P. Kolb, Y.Y. Ma, L. Yang, Z.Y. Yao
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
S.H. Abidi
University of Toronto, Toronto, Ontario, Canada
R. Kiefl
UBC & TRIUMF, Vancouver, British Columbia, Canada

MuSR is a powerful tool to probe local magnetism and hence can be used to diagnose flux penetration in Type-II superconductors. Samples produced at TRIUMF and with collaborators in both coin shaped and ellipsoidal geometries have been characterized by applying either transverse or parallel fields between 0 and 300mT and measuring flux entry as a function of applied field. Samples include Nb treated in standard ways including forming, chemistry, and heat treatments. Further, Nb samples have been doped with Nitrogen and coated with a 2 micron layer of Nb3Sn by collaborators from FNAL and Cornell respectively and measured in three field/geometry configurations. Analysis of the method in particular the effects of geometry and the role of pinning will be presented. Results of the measurements will be presented.

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MOPB051

Muon Spin Rotation on Treated Nb Samples in Parallel Field Geometry

210

S. Gheidi
UBC, Vancouver, B.C., Canada
T.J. Buck, T. Junginger, R.E. Laxdal, G. Morris
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
M. Dehn
TUM/Physik, Garching bei München, Germany
R. Kiefl
UBC & TRIUMF, Vancouver, British Columbia, Canada

MuSR is a powerful tool to probe local magnetism and hence can be used to diagnose the entry of magnetic flux in superconductors. First measurements on SRF samples were done with an external DC field applied perpendicular to the sample1 (transverse geometry) with the muons applied to the sample face. Here the results are strongly impacted by demagnetization, pinning strength and edge effects. A new spectrometer has been developed to allow sample testing with a field varying from 0 to 300mT applied along the sample face (parallel geometry) analogous to rf fields in SRF resonators. The geometry is characterized by a small demagnetization factor reducing the impact of pinning and edge effects on field of first flux entry. The beamline installation and first results comparing transverse and parallel results will be presented.
1 Grassellino et al. Muon spin rotation studies of niobium for superconducting rf applications.
Phys. Rev. ST Accel. Beams, 16:062002, Jun 2013.

Poster MOPB051 [0.719 MB]

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TUPB041

Testing Nb3Sn Coating Using muSR

651

R.E. Laxdal, T.J. Buck
TRIUMF, Canada's National Laboratory for Particle and Nuclear Physics, Vancouver, Canada
S. Gheidi
UBC, Vancouver, B.C., Canada
R. Kiefl
UBC & TRIUMF, Vancouver, British Columbia, Canada
M. Liepe, S. Posen
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

The SRF group at TRIUMF has tested samples relevant for SRF application since 2010 using the TRIUMF μSR facility. In this study collaborators at Cornell coat a Nb coin and a Nb ellipsoid sample with Nb3Sn for characterization using μSR at TRIUMF. Field of first flux entry measurements are performed at M20 on both samples. Measurements include the vortex nucleation field Hnucleate and Tc of both Nb3Sn and Nb. Interestingly the Nb3Sn increases the vortex nucleation field at 2K over standard Nb samples.

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reference for this paper to ※ BibTeX, ※ LaTeX, ※ Text, ※ RIS/RefMan, ※ EndNote (xml)