Dissertation / PhD Thesis

GSI-2025-00816

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Transverse excitation for beam diagnostics and slow extraction from synchrotrons

Niedermayer, P. (Corresponding author)GSI* ; Franchetti, G. (Thesis advisor)GSI* ; Ratzinger, U. (Reviewer) ; Najmudin, Z. (Reviewer)

2025
Universitätsbibliothek Johann Christian Senckenberg Frankfurt am Main

Please use a persistent id in citations: urn:nbn:de:hebis:30:3-913001

Abstract: Transverse excitation is a key method required for the operation of synchrotrons, a type of circular particle accelerator suitable for a wide range of applications. The excitation is essential to control the beam: First, it is used in the context of beam diagnostics to enable monitoring of the accelerator's working point (tune). This is required to setup the machine and to avoid unintentional beam losses. Second, it is used in the context of resonant slow extraction to drive and control the extraction of particles from the accelerator. This method referred to as Radio Frequency Knock Out (RF-KO) enables the delivery of defined beam intensities for experiments or medical treatments. Transverse excitation is performed by creating a time-dependent electromagnetic field through which particles are deflected on each subsequent turn in the synchrotron. To generate this dipolar field with frequencies in the radio frequency (RF) domain, signal generators, amplifiers and stripline kickers (exciters) are utilized.This thesis comprises a detailed study of the method of transverse excitation. Special focus is placed on the nonlinear beam dynamics, the composition and generation of the excitation signal and the peripheral systems (detectors, exciters). An excitation system for tune diagnostics and one for resonant slow extraction is developed and used to study different methods for transverse excitation experimentally. Particle tracking simulations are carried out to gain a detailed understanding of the excitation process. Based on the findings from experiments and simulations, recommendations are given for the improved application of excitation techniques. Two new excitation methods for resonant slow extraction are developed, studied and compared to other commonly applied methods. The sensible application of these excitation techniques is essential to improve the quality of the particle beam and the operation and performance of the synchrotron.

Note: Dissertation, Goethe Uni Frankfurt, 2025

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Contributing Institute(s):

1. HESR (HES)
2. Beam Diagnostics (BEA)
3. Ring RF (RRF)

Research Program(s):

1. 621 - Accelerator Research and Development (POF4-621) (POF4-621)
2. I.FAST - Innovation Fostering in Accelerator Science and Technology (101004730) (101004730)

Experiment(s):

1. External experiment at external facility/ no experiment at GSI (other)
2. Experiment at GSI without experiment proposal number ( - ; Facility_outside_beam_time_program )

Appears in the scientific report 2025

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