OFFSET: Optical Fiber Folded Scintillating Extended Tracker

The OFFSET collaboration aims at the development of a novel system for tracking charged particles, designed to achieve real-time imaging, large detection areas, and a high spatial resolution especially suitable for use in medical diagnostics. This paper presents the first prototype of this tracker, having a 20×20 cm2 sensitive area made by two crossed ribbons of 500μm square scintillating fibers. The track position information is extracted in real time using a reduced number of read-out channels to obtain very large detection area at moderate cost and complexity. The performance of the tracker was investigated using β sources, cosmic rays and a 62 MeV proton beam

YAG(Ce) crystal characterization with proton beams

A YAG(Ce) crystal has been characterized with a proton beam up to 100 MeV. Tests were performed to investigate the possibility of using this detector as a proton calorimeter. A crystal size has been chosen that is able to stop up to 200 MeV. Energy resolution and light response have been measured at Laboratori Nazionali del Sud with a proton beam up to 60 MeV and a spatial homogeneity study of the crystal has been performed at Loma Linda University Medical Center with a 100 MeV proton beam. The YAG(Ce) crystal showed a good energy resolution equal to 3.7% at 60 MeV and measurements, performed in the 30–60 MeV proton energy range, were fitted by Birks' equation. Using a silicon tracker to determine the particle entry point in the crystal, a spatial homogeneity value of 1.7% in the light response has been measured

Monte Carlo evaluation of the Filtered Back Projection method for image reconstruction in proton computed tomography

In this paper the use of the Filtered Back Projection (FBP) Algorithm, in order to reconstruct tomographic images using the high energy (200–250 MeV) proton beams, is investigated. The algorithm has been studied in detail with a Monte Carlo approach and image quality has been analysed and compared with the total absorbed dose. A proton Computed Tomography (pCT) apparatus, developed by our group, has been fully simulated to exploit the power of the Geant4 Monte Carlo toolkit. From the simulation of the apparatus, a set of tomographic images of a test phantom has been reconstructed using the FBP at different absorbed dose values. The images have been evaluated in terms of homogeneity, noise, contrast, spatial and density resolution

Tomographic images by proton Computed Tomography system for proton therapy applications

Proton therapy is a highly precise form of cancer treatment, which requires accurate knowledge of the dose delivered to the patient and verification of the correct patient position to avoid damage to critical normal tissues. The development of pCT (proton Computed Tomography) system represents an important feature for precise proton radiation treatment planning because it could permit the direct measurement of the proton stopping power distribution, improving the accuracy in dose calculus, and the patient's position. A pCT prototype was manufactured in order to demonstrate the capability to acquire, during treatments in proton therapy centers, radiographic and tomographic images according to clinical demands

The Energy Selection System for the laser-accelerated proton beams at ELI-Beamlines

ELI-Beamlines is one of the four pillars of the ELI (Extreme Light Infrastructure) pan-European project. It will be an ultrahigh-intensity, high repetition-rate, femtosecond laser facility whose main goals are the generation and applications of high-brightness X-ray sources and accelerated charged particles. In particular medical and multidisciplinary applications with laser-accelerated beams are treated by the ELIMED task force, a collaboration between different research institutes. A crucial goal for this network is represented by the design and the realization of a transport beamline able to provide ion beams with suitable characteristics in terms of energy spectrum and angular distribution in order to perform dosimetric tests and biological cell irradiations. A first prototype of transport beamline has been already designed and some magnetic elements are already under construction. In particular, an Energy Selector System (ESS) prototype has been already realized at LNS-INFN. This paper reports about the studies of the ESS properties as, for instance, energy spread and transmission efficiency, carried out using the GEANT4 Monte Carlo code

Towards a proton imaging system

Hadron therapy for tumor treatment is nowadays used in several medical centres. The main advantage in using protons or light ions beams is the possibility of tightly shaping the radiation dose to the target volume. Presently the spatial accuracy of the therapy is limited by the uncertainty in stopping power distribution, which is derived, for each treatment, from the photon attenuation coefficients measured by X-ray tomography. A direct measurement of the stopping powers will help in reducing this uncertainty. This can be achieved by using a proton beam and a detection system able to reconstruct a tomography image of the patient. As a first step towards such a system an apparatus able to perform a proton transmission radiography (pCR) has been designed. It consists of a silicon microstrip tracker, measuring proton trajectories, and a YAG:Ce calorimeter to determine the particle residual energy. Proton beam and laboratory tests have been performed on the system components prototypes: the main results will be shown and discussed.</br