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arXiv · 2501.14690

Upgrades and maintenance of the CRYRING@ESR electron cooler for improved internal electron target operation

Athanasios Koutsostathis·Claude Krantz·Elena-Oana Hanu·Frank Herfurth·Regina Heß·Wolfgang Kaufmann·Michael Lestinsky·Mirko Dieter Looshorn·Esther Babette Menz·Andreas Reiter·Jon Roßbach·Stefan Schippers·Phe Man Suherman
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Abstract

The electron cooler of the CRYRING@ESR storage ring at the GSI-FAIR accelerator complex is a unique instrument, which not only provides beam cooling of the stored ions, but also serves as a low-energy electron target for Dielectronic Recombination experiments. The minimisation of vacuum contamination and the response to rapid energy changes are key requirements of the cooler in electron target mode. Therefore, a test bench was prepared to study the outgassing behaviour of the electron gun components and a setup was constructed to evaluate the drift-electrode-modulation of the acceleration voltage of the cooler. The vacuum studies showed that the electron gun cathode was severely malfunctioning and resulted in its replacement. The drift-electrode-modulation of the acceleration voltage showed significant improvements compared to direct modulation of the terminal voltage of the cooler.

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Athanasios Koutsostathis, Claude Krantz, Elena-Oana Hanu, Frank Herfurth, Regina Heß, Wolfgang Kaufmann, Michael Lestinsky, Mirko Dieter Looshorn, Esther Babette Menz, Andreas Reiter, Jon Roßbach, Stefan Schippers, Phe Man Suherman. 2025-01-24. Upgrades and maintenance of the CRYRING@ESR electron cooler for improved internal electron target operation. https://doi.org/10.12681/hnpsanp.7988

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