IPAC2017 - List of Authors (Koufalis, P.N.)

Paper	Title	Page
WEPVA145	Analysis of Mean Free Path and Field Dependent Surface Resistance	3609
	J.T. Maniscalco, F. Furuta, D.L. Hall, P.N. Koufalis, M. Liepe Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
	Funding: NSF-PHY 1416318 Work from Cornell in 2016 built on recent theoretical research in the field of SRF to link the electron mean free path to the field-dependent BCS surface resistance. This research relates the magnitude of the ‘‘anti-Q-slope'', the puzzling reduction of surface resistance with increasing RF field intensity observed in certain cavities, to the doping level of nitrogen-doped niobium, quantified by the mean free path: shorter mean free paths correspond directly with stronger anti-Q-slopes. The theoretical connection comes through the overheating of the quasiparticles, which more effectively transfer their energy to the lattice at short mean free paths. In this report, we present an update of this analysis, investigating recent test results of low-temperature-doped single-cell and nine-cell cavities. We also study the theoretical implications for cavities at frequencies higher and lower than the often-studied 1.3~GHz.
DOI •	reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPVA145
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Paper

Title

Page

Analysis of Mean Free Path and Field Dependent Surface Resistance

3609

J.T. Maniscalco, F. Furuta, D.L. Hall, P.N. Koufalis, M. Liepe
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA

Funding: NSF-PHY 1416318
Work from Cornell in 2016 built on recent theoretical research in the field of SRF to link the electron mean free path to the field-dependent BCS surface resistance. This research relates the magnitude of the ‘‘anti-Q-slope'', the puzzling reduction of surface resistance with increasing RF field intensity observed in certain cavities, to the doping level of nitrogen-doped niobium, quantified by the mean free path: shorter mean free paths correspond directly with stronger anti-Q-slopes. The theoretical connection comes through the overheating of the quasiparticles, which more effectively transfer their energy to the lattice at short mean free paths. In this report, we present an update of this analysis, investigating recent test results of low-temperature-doped single-cell and nine-cell cavities. We also study the theoretical implications for cavities at frequencies higher and lower than the often-studied 1.3~GHz.

DOI •

reference for this paper ※ https://doi.org/10.18429/JACoW-IPAC2017-WEPVA145

Export •

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