• Electromagnetic simulation of radiofrequency cavities for future particle accelerators
• Wakefields and Beam-Cavity interaction
• Cavity powering in the presence of beam
• Particle accelerator design
• Particle beam dynamics

The LHC at CERN is currently accelerating protons to an energy of 14 TeV. After an upgrade in the coming years, the number of collisions will be greatly increased, while retaining the same collision energy. This new configuration is planned to run until the 2040s, at which point a new facility would be needed for further discoveries. The international muon collider collaboration is investigating the possibility for a particle accelerator using muons. The muon is a fundamental particle classified as a lepton with a mass 207 times larger than an electron. One of the main limitations of circular electron accelerators is the energy lost by synchrotron radiation. As the radiation scales with the mass of the particle, the lost energy of a muon is lower by a factor of around 10^9. In comparison to a proton accelerator, the required magnetic field strength is lower due to the smaller mass of the muon. This reduces the size of a circular facility, as a bending radius can be reduced at the same field strength. The main limitation of using muons is the lifetime of 2.2us. For this reason, the muon must be accelerated quickly to its collision energy before it decays. The required gradients and energy gains per turn provide a challenge for the radio frequency system and the beam dynamics.

The aim of the project is to design a baseline RF scheme for the rapid cycling synchrotrons in the muon acceleration chain. One of the challenges of the project lies in the fact, that the particle bunches are large, leading to transient beam loading effects, which have a significant impact on the acceleration and cavity powering. The bunch intensity also leads to large higher order mode (HOM) power, which needs to be dissipated within the repetition period of 200 ms.
https://muoncollider.web.cern.ch/

Supervisor:
Prof. Dr. rer. nat. habil. Ursula van Rienen