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DOE OSTI · 2562848

Mitigating field emission in SSR2 cryomodules for PIP-II

Parise, Mattia [Fermilab]
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Abstract

The SSR2 cavities for PIP-II have consistently been affected by field emission since the first cold tests with the unity coupler. A comprehensive root cause analysis was conducted to investigate the origin of this issue and to identify the fabrication, processing, and handling factors that have the greatest impact on field emission onset. New techniques were developed and effectively implemented to achieve field emission-free SSR2 cavities. In addition, effort was dedicated both to relating the radiation level measured at the test stand with the expected levels in the LINAC tunnel and to understand the evolution of field emission through the assembly steps. The challenge of overcoming field emission also led to a reassessment of design choices, enhancing our understanding of their effects on cavity performance.

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Parise, Mattia [Fermilab]. 2025-04-11. Mitigating field emission in SSR2 cryomodules for PIP-II. https://doi.org/10.2172/2562848

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