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arXiv · 1605.06494

Cryogenic rf test of the first plasma etched SRF cavity

J. Upadhyay·A. Palczewski·S. Popović·A. -M. Valente-Feliciano·D. Im·L. Phillips·L. Vušković
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Abstract

Plasma etching has a potential to be an alternative processing technology for superconducting radio frequency (SRF) cavities. An apparatus and a method are developed for plasma etching of the inner surfaces of SRF cavities. To test the effect of the plasma etching on the cavity rf performance, a 1497 MHz single cell SRF cavity is used. The single cell cavity is mechanically polished, buffer chemically etched afterwards and rf tested at cryogenic temperatures for a baseline test. This cavity is then plasma processed. The processing was accomplished by moving axially the inner electrode and the gas flow inlet in a step-wise manner to establish segmented plasma processing. The cavity is rf tested afterwards at cryogenic temperatures. The rf test and surface condition results are presented.

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J. Upadhyay, A. Palczewski, S. Popović, A. -M. Valente-Feliciano, D. Im, L. Phillips, L. Vušković. 2016-05-20. Cryogenic rf test of the first plasma etched SRF cavity. https://arxiv.org/abs/1605.06494

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