• Bira, S.; Longuevergne, D.; Keckert, S.; Kugeler, O.; Knobloch, J.; Proslier, T.; Kalboussi, Y.: Multipacting Analysis of the Quadripolar Resonator (QPR) at HZB. In: Kenji Saito ... [Ed.] : SRF2021 : Proceedings of the 20th International Conference on RF Superconductivity, virtuell, 27 June 2021 to 2 July 2021Geneva: JACoW, 2021. - ISBN 978-3-95450-233-2, p. SUPCAV013/1-4

Open Access Version

Abstract:
Multipacting (MP) is a resonating electron discharge, often plaguing radio-frequency (RF) structures, produced by the synchronization of emitted electrons with the RF fields and the electron multiplication at the impact point with the surface structure. The electron multiplication can take place only if the secondary emission yield (SEY, i.e. the number of electrons emitted due to the impact of one incoming electron), is higher than 1. The SEY value depends strongly on the material and the surface contamination. Multipacting simulations are crucial in high frequency (HF) vacuum structures to localize and potentially improve the geometry. In this work, multipacting simulations were carried out on the geometry of the Quadrupole Resonator (QPR) in operation at HZB using the Spark 3D module in Microwave Studio suite (CST). These simulations helped to understand a particular behavior observed during the QPR tests, and furthermore made it possible to suggest enhancement ways in order to limit this phenomenon and facilitate its operation.