Development of a time-of-flight ion computed tomography system based on ultra-fast silicon sensors

Speaker: Felix Ulrich-Pur
Institution: Austrian Academy of Sciences, Institute of High Energy Physics(HEPHY), Austria, and GSI Helmholtzzentrum für Schwerionenforschung, Germany

Abstract

Over the last few years, several ion computed tomography (iCT) demonstrator systems have emerged showing the potential of iCT to improve the treatment planning quality for ion beam therapy. Although their results are promising, no clinical system exists so far, which is mainly due to the demanding data rate requirements to keep the acquisition time in a clinically useful timespan (~min). To meet this challenge, we have investigated a novel iCT design concept based on ultra-fast silicon detectors (UFSDs), also known as low gain avalanche detectors (LGADs), which are fast particle detectors especially designed for high-rate environments. Paired with an excellent timing precision ( >=30ps) and high spatial granularity (>=50µm), UFSDs allow to reconstruct single-particle tracks even with a high track multiplicity, thus improving the rate capability. First, we will give an overview of the different scanner design concepts. For that purpose, we have created a Monte Carlo (MC) model of a realistic system based on UFSDs and studied the influence of different system parameters on the stopping power accuracy and precision. Those setups include a conventional iCT system with a time-of-flight (TOF) based calorimeter and a novel design concept, which does not require a residual calorimeter. Second, we present our hardware development efforts towards the first TOF-iCT demonstrator and show first proof-of-principle measurements, which were conducted at the MedAustron particle and therapy centre in Austria. Finally, we will discuss the challenges and future plans to build a clinical TOF-iCT system.

Resources