5th Slow Extraction Workshop at MedAustron in Wiener Neustadt

The main magnet power supplies for the J-PARC Main Ring were upgraded from 2021 to 2023. In addition to increasing the maximum voltage output to shorten the acceleration time from 3GeV to 30GeV, reducing the current ripples for improving the beam spill structure was also one of the major objectives of the power supply upgrade. Although good results were obtained in current ripple measurements...

Inevitably, to evaluate the quality of the slow extracted beams delivered to experiments, we need to understand how different frequency components develop. How we evaluate this is to look at the beam spills in a beamline. However, while those are the end result and what the experiments see, they don’t directly represent how the different frequencies get imprinted into the spill. This is what...

Spill uniformity is a key performance metric for the experimental users in the CERN North Area, who receive slow-extracted protons from the Super Proton Synchrotron. In this contribution, RF empty-bucket techniques are studied to suppress the low-frequency variations in the spill caused by power-converter ripple. The study includes simulation, measurement and the long-term experience after...

The intensity ripples in the extracted beam are a crucial topic for clinical treatment, as a constant particle flux is required for optimal operation of the accelerator within safety regulations. Therefore, ripple mitigation techniques are widely used in facilities worldwide.
This talk discusses the intensity ripples at MedAustron by analysing the ripple frequency spectrum and the impact of...

In this talk, we investigate the transit time of particles in a third-integer resonant extraction process. Transit time is defined as the number of turns a particle takes to get extracted once it is in the unstable region, i.e., outside the triangular separatrix. The study of transit time is important because transit time determines the beam response time during resonant extraction and thus...

The Heidelberg Ion-Beam Therapy Centre HIT uses the RF-KO slow extraction method to extract the particles from the synchrotron. To improve the spill quality of the extracted beam a new RF-signal was investigated which increases the R-value from 92.5% to 97.5%. The signal is a multiband RF signal broadened with a random BPSK at 3 frequency bands. The new KO-DDS which generates the signal is in...