Advanced RF techniques for CERN's future slow-extracted beams

Thesis

Resonant slow extraction is a technique employed to provide long pulses of particles from synchrotrons. It is exploited in a wide variety of applications, such as experimental physics, hadron therapy and irradiation testing. At the CERN Super Proton Synchrotron (SPS), the technique is exploited to deliver beam to the fixed-target experiments in the North Area. In order to improve current operation and prepare for future requests, the slow-extraction system in the SPS would benefit from further optimisation and flexibility. More specifically, millisecond-scale modulations in the extracted flux are known to compromise experimental data taking. This is an issue common to all facilities that perform slow extraction and mitigation techniques need to be pursued. Additionally, a future experimental request known as Search for Hidden Particles (SHiP) will require a particle spill with a customised time structure in the nanosecond-scale. It is important to propose strategies to deliver such a beam within the constraints of the SPS system. This thesis will study the exploitation of an advanced RF technique known as empty-bucket channelling to address these challenges. In particular, it will employ a simulation model to systematically characterise the manipulation. The results will then be benchmarked with measurement. Finally, an operational implementation will be proposed.

Authors: Arrutia Sota, PA

• DOI: 10.5287/ora-6ro94njbe
• Type of award: DPhil
• Level of award: Doctoral
• Awarding institution: University of Oxford
• Language: English
• Keywords: slow extraction; beam dynamics; accelerator physics
• Subjects: Beam dynamics