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arXiv · 2508.11253

RF characterization and beam measurements with 3D printed Fast Faraday Cups

Stephan Klaproth·Rahul Singh·Samira Gruber·Lukas Stepien·Herbert De Gersem·Andreas Penirschke
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Abstract

The early stages of most particle accelerator chains produce sub-ns bunches with velocities in the range of 1 to 20% of the speed of light. Fast Faraday Cups (FFC) are designed to measure the longitudinal charge distribution of these short bunches of free charges. Coaxial designs have been utilized at the GSI's linear accelerator UNILAC to characterize ion bunches with bunch lengths ranging from a few hundred ps to a few ns. The typical design goals are to avoid the pre-field of the charges and to suppress secondary electron emission, while retaining the capability of bunch-by-bunch measurements. In this contribution, a novel FFC design manufactured using additive manufacturing, e.g. laser powder bed fusion is presented and compared with a traditionally produced FFC. The design considerations, RF characterization, and selected measurements with ion beam at GSI are shown.

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Stephan Klaproth, Rahul Singh, Samira Gruber, Lukas Stepien, Herbert De Gersem, Andreas Penirschke. 2025-08-15. RF characterization and beam measurements with 3D printed Fast Faraday Cups. https://arxiv.org/abs/2508.11253

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