HUST, Wuhan, People’s Republic of China
Shenzhen Institute of Computing Science, Shenzhen, People’s Republic of China
Canted-Cosine-Thera (CCT) superconducting magnet is a promising alternative for normal-conducting magnets in compact accelerator systems such as large hadron colliders or particle therapy facilities. For the convenience of lattice design with CCT, we develop the CCT Simulation and Particle Tracking (CSPT) toolkit. It’s a program that can perform both simulations of the beam dynamic process within particle accelerators and basic electromagnetic harmonic analysis. The charged-particle tracking and electromagnetic calculation process can be accelerated by either CPU multicore or GPU parallel, with a maximum speed-up ratio of 457. The simulation result of the program is well consistent with Opera and COSY Infinity.
PSI, Villigen PSI, Switzerland
In proton therapy (PT), high dose rates could allow efficient utilization of motion mitigation techniques for moving targets, and potentially enhance normal tissue sparing due to the FLASH effect. Cyclotrons are currently the most common accelerator for PT, accounting for two-thirds of the total installations. However, for cyclotron-based facilities, high dose rates are difficult to reach for low-energy beams, which are generated by passing a high-energy beam through an energy degrader and an energy selection system (ESS); due to scattering and range straggling in the degrader, the emittance and energy/momentum spread increase significantly, incurring large losses from the cyclotron to the patient position. To solve these problems, we propose two approaches: a) transporting the maximum acceptable emittance in both transverse planes (using asymmetric collimators and/or scattering foil); b) an ESS with a wedge (instead of slits), reducing the momentum spread of the beam without significant beam losses. We demonstrate in simulation that low-energy beam transmission can be increased up to a factor of 60 using these approaches compared to the currently used beamline and ESS. This concept is key to enhance the potential of proton therapy by increasing the possibilities to treat new indications in current and future proton therapy facilities while reducing the cost.
iThemba LABS, Somerset West, South Africa
Using a Belmont-Pabot spiral inflector for axial beam injection presents difficulties when matching the beam emittance to the cyclotron acceptance. For an electrostatic inflector one of the potential solutions to this problem is to use transverse electric field gradients to influence and optimise the optics. Here we extend this approach to magnetic spiral inflectors. It is demonstrated that the gradient of the magnetic field along the central trajectory can be controlled by an appropriate permanent magnet inflector design, and that these gradients have a large influence on the optics. The transverse gradients are numerically optimised and the performance compared to an optimised electrostatic spiral inflector. A faster numerical method for accurately determining the electric field of an electrostatic inflector is also presented.