Speaker
Mr
Daniel Koser
(IAP Goethe University Frankfurt)
Description
The High Charge State Injector (HLI) at the GSI Helmholtz Centre for Heavy Ion Research in Darmstadt, Germany, serves as one of the two injector linacs for the UNILAC as well as dedicated injector for the upcoming cw linac project for super heavy element research. As the front end of the HLI is planned to be upgraded for cw operation a newly revised cw capable RFQ structure with an operating frequency of 108 MHz is required. The existing 4-rod structure, which was commissioned at the HLI in 2010, suffers from severe modulated rf power reflections originating from mechanical oscillations of the electrodes that both limit the achievable performance and impede stable operation. Besides preceding vibration measurements that were done by GSI using a laser vibrometer, the structural mechanical behavior of the 4-rod geometry was extensively analyzed using ANSYS. Thereby the crucial mechanical eigenmodes could be identified and their impact on the rf properties was investigated by simulations using CST MWS. A completely newly revised 4-rod RFQ design with optimized structural rigidity was developed of which a 6-stem prototype is currently being manufactured.
Primary author
Mr
Daniel Koser
(IAP Goethe University Frankfurt)
Co-authors
Prof.
Holger Podlech
(IAP University of Frankfurt)
Dr
Lars Groening
(GSI Helmholtz Centre)
Prof.
Oliver Kester
(TRIUMF)
Dr
Peter Gerhard
(GSI Helmholtz Centre)
