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arXiv · 2002.11755

Stable CW Operation of Nb$_3$Sn SRF Cavity at 10 MV/m using Conduction Cooling

Neil Stilin·Adam Holic·Matthias Liepe·Ryan Porter·James Sears
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Abstract

Superconducting radio-frequency (SRF) accelerating cavities are a promising technology for compact, high-power, MeV-scale accelerators, providing continuous beam operation for a wide range of potential applications in industry, medicine, national security, and science. However, SRF cavities have traditionally been cooled using complex and expensive cryogenic infrastructure, which has been a significant obstacle in employing this powerful technology in small-scale systems. With the recent progress on high-performance Nb$_3$Sn-coated SRF cavities and the introduction of cryocoolers, which can provide turn-key style conduction cooling below 4.2 K, this barrier can now be overcome. At Cornell University, we have developed a prototype setup that utilizes a commercial cryocooler to provide the necessary cooling for operation of a 2.6 GHz Nb$_3$Sn-coated SRF cavity. We have now demonstrated first stable operation in continuous mode at accelerating fields up to 10 MV/m with a quality factor of Q$_0$ = 4x10$^9$, thereby achieving an important milestone in making turn-key SRF a reality.

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Neil Stilin, Adam Holic, Matthias Liepe, Ryan Porter, James Sears. 2020-02-26. Stable CW Operation of Nb$_3$Sn SRF Cavity at 10 MV/m using Conduction Cooling. https://arxiv.org/abs/2002.11755

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