Compact superconducting 250 MeV proton cyclotron for the PSI PROSCAN proton therapy project

Abstract

A cyclotron for proton therapy has to fulfil many requirements set by the specific operational and safety needs of a medical facility and the medical environment. These are for instance high extraction efficiency, high availability and reliability, simple and robust operation. ACCEL Instruments GmbH has refined the design concept of a medical cyclotron for the PSI PROSCAN project with the objective to use this cyclotron as the standard accelerator in complete proton therapy facilities, which ACCEL intends to market.Starting from the design in [1], we have carried out further detail clarifications, optimizations and adaptations to the needs of PSI [2]. The work was performed in a collaboration between ACCEL, NSCL and KVI in view of the requirements from the PSI PROSCAN project. An overview on the design will be given touching on subjects such as the 3D structural analysis of the coil, detailed magnetic modeling for optimization of the inner region and the spiral, optimization of the RF power, optimization of the cryogenic design based on available cryocoolers instead of a liquefaction plant and Monte Carlo simulations to estimate the heat balance produced by neutrons at 4K components.

Isochronism of the ACCEL 250MeV medical proton cyclotron

“…Based on a proposal originating from 1993, ACCEL Instruments GmbH has designed a superconducting cyclotron for proton therapy in close collaboration with the National Superconducting Cyclotron Laboratory (NSCL) [1,2]. The cyclotron is a four sector azimuthally varying field isochronous superconducting compact machine with a central magnetic induction of 2:4 T and an extraction radius of 815 mm.…”

Automated cyclotron tuning using beam phase measurements

“…For application in the field of proton therapy ACCEL developed a new 250 MeV superconducting cyclotron in cooperation with the National Superconducting Cyclotron Laboratory in Michigan, USA [1]. The first two cyclotrons of this type have been commissioned successfully and are integrated in proton therapy facilities, one at the Paul Scherrer Institute (PSI) in Switzerland and one at the Rinecker Proton Therapy Center (RPTC) in Germany [2].…”

Superconducting 250 MeV Proton Cyclotron for Cancer Treatment

“…The purpose of both machines is to produce 250 MeV protons for cancer treatment. Based on a conceptual design of NSCL [1], [2] these machines are the first ones of its kind being engineered and built by industry.…”