Title: The development of a novel detector for the measurement of radiobiological effect of ion beams
Funder: Department of Health (England)

Abstract: This project proposes to take the early stage prototype detector developed in the initial i4i grant and develop it further into robust metrology devices which may be used in centres for particle therapy world-wide. There is no such device currently available and with an increasing number of centres for particle therapy being planned or developed worldwide, there is a growing market for such devices. The prototypes developed in this project, which will have different sizes, will be used with a variety of low-Z ions (e.g. H, He, Li, C, O, Cl) and particle energies to investigate and characterise their response for each of these particle types. This will provide essential data to define the optimal design as a function of particle type, dose-rate and energy. Experiments for different irradiation regimes such as different particle count rates, radiation striking different areas or components of the prototype detectors and broad beam conditions will be executed to establish the performance of the microbolometers and quantify potential signal distortion effects such as spurious pulses and pulse pile up. The operational characteristics will be evaluated extensively in order to be able to propose and develop a configuration that can lead to a practical, useable device in a clinical environment. The experimental data obtained will provide benchmark information to test previously obtained Monte Carlo simulation results and will be used to refine these simulations. The refined simulation models will then allow more detailed modelling and in-depth study of all the aspects that affect the performance and microdosimetric characteristics of the devices. The refined simulations will also enable the quantitative study of any corrections that may need to be applied to raw measurement data. Thermal modelling using finite element methods to solve the heat equation, performed in the previous pilot study, will also be refined based on the experimental data. The refined Monte Carlo simulations will feed in data to make the theoretical thermal characterisation more realistic. These will also form an essential step in establishing quantitative corrections accounting for heat transfer phenomena to the measurements. The combined information from experiments, Monte Carlo simulations and thermal modelling will lead to the formulation and production of an improved design (or a range of designs depending on the application area such as particle type, beam energy, irradiation regimes) that has also the necessary flexibility, transportability and versatility to be used in a clinical environment. This improved design will then be extensively tested and characterised in our in-house ion beams at the Surrey Ion Beam Centre and subsequently applied in clinical beam situations at selected ion beam centres worldwide. The development of the detector into a commercial product or its use in a commercial metrology service, will also be investigated, in collaboration with dedicated Research Enterprise groups at Surrey University and the National Physical Laboratory.


Research activity codes: 5.5 RADIOTHERAPY AND OTHER NON-INVASIVE THERAPIES
Health categories: CANCER AND NEOPLASMS