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This paper describes the development of a proton Computed Tomography (pCT) apparatus able to reconstruct a map of stopping power useful for accurate proton therapy treatment planning and patient positioning. This system is based on two main components: a silicon microstrip tracker and a YAG:Ce crystal calorimeter. Each proton trajectory is sampled by the tracker in four points: two upstream and two downstream the object under test; the particle residual energy is measured by the calorimeter. The apparatus is described in details together with a discussion on the characterization of the hardware under proton beams with energies up to 175 MeV.

The design and the characterization of a calorimeter system, aimed at measuring the residual energy in a proton Computed Tomography (pCT) apparatus, is described. The calorimeter has a 6 × 6 cm2 active area to fully cover the tracker area of the pCT system, being 10 cm thick it is able to stop up to 200 MeV protons and sustain 1 MHz particle rate (average rate on the whole area). The YAG(Ce) scintillator is promising for charged particle detection applications where high-count rate, good energy resolution and compact photodiode readout, not influenced by magnetic fields, are of importance. The aim of this work is to show data acquired with proton beam energy up to 175 MeV and to discuss the performances of this calorimeter.

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 500 μ m 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.

A YAG:Ce calorimeter with a 6×6 cm2 active area, long 10 cm has been manufactured in order to stop up to 200 MeV protons and to sustain 1MHz particle rate. It consists of four optically separated crystals assembled in the same housing. The YAG:Ce scintillator is promising for charged particle detection applications where high-count rate, good energy resolution and compact photodiode readout, not influenced by magnetic fields, are of importance. The YAG:Ce calorimeter has been characterized with proton beams up to 175MeV a The Svedberg Laboratory (TSL), Uppsala Sweden. Results obtained are shown and discussed.

In this paper we describe a new detection system for the high resolution measurement of the residual range of charged particles, designed and developed with the aim of achieving real-time data acquisition and large detection areas. A prototype of the residual range detector, with a sensitive area of about 4 × 4 cm2, consisting of a stack of sixty ribbons of scintillating fibers (Sci-Fi) has been designed and tested. Each layer is read-out by two wavelength shifter (WLS) fibers and a position sensitive photomultiplier (PSPM). The Bragg peak shape is calculated real-time by the time over a suitable threshold for each channel. The results of the measurements taken using the prototype and a 62 MeV proton beam and a comparison with the GEANT4 simulations of the detector are presented. The main concepts on which the prototype is based have been used to demonstrate the technique patented by the INFN. The next step will be to design and validate the final detector which will have 30 × 30 cm2 FOV and cover the 250 MeV proton range with about 150 micron range resolution. These performances are suitable for almost all medical imaging applications.

The design of a detector for tracking charged particles is presented together with the characterization techniques developed to extract the main design specifications. The goals for the final detector are to achieve real-time imaging performances, a large detection area, and a high spatial resolution, particularly suitable for medical imaging applications. This paper describes the prototype of the tracker plane, which has a 20 × 20 cm2sensitive area consisting of two crossed ribbons of 500 μm square scintillating fibers. The information about the hit position extracted real-time tracker in an innovative way, using a reduced number of the read-out channels to obtain a very large detection area but with moderate costs and complexity. The performances of the tracker have been investigated usingβsources, cosmic rays, and a 62 MeV proton beam.

Proton Computed Tomography (pCT) is a medical imaging technique based on the use of proton beams with energies above 200 MeV to directly measure stopping power distributions inside the tissue volume. Prima (PRoton IMAging) is an Italian collaboration working on the development of a pCT scanner based on a tracker and a calorimeter to measure single protons trajectory and residual energy. The tracker is composed of four planes of silicon microstrip detectors to measure proton entry and exit positions and angles. Residual energy is measured by a calorimeter composed of YAG:Ce scintillating crystals. A first prototype of pCT scanner, with an active area of about 5×5 cm2, has been constructed and characterized with 60 MeV protons at the INFN Laboratori Nazionali del Sud, Catania (Italy) and with 180 MeV protons at Svedberg Laboratory, Uppsala (Sweden). A new pre-clinical prototype with an extended active area up to 20×5 cm2, real time data acquisition and a data rate up to 1 MHz is under development. A description of the two prototypes will be presented together with first results concerning tomographic image reconstruction.

The PRIMA (Proton IMAging) experiment is aimed at developing a proton Computed Tomography (pCT) prototype based on tracking single protons. Approaches to the pCT consist in the use of silicon microstrip detectors to measure the position and direction of individual protons before and after they traverse the phantom, in view to reconstruct the trajectory of each proton, and a calorimeter for measuring particle residual energy. A small prototype was tested, under 62 MeV proton beam at Laboratory Nazionali del Sud, (Catania Italy) and under 180 MeV proton beam at Svedberg Laboratories, Uppsala Universitet, (Uppsala Sweden). Several experiments concerning proton imaging, tomography and radiography, were carried out during these beam tests. Radiographies have been reconstructed with different methods: results show the good performances of the device, with spatial resolution fulfilling the stringent requirements of a pCT device.

This paper presents the design flow of a detector for tracking charged particles together with the characterization techniques developed to extract the main design specifications. The goals for the final detector are to achieve real-time imaging, a large detection area and a high spatial resolution particularly suitable for medical imaging applications. The main concepts have been patented by the INFN. This paper describes the prototype tracker, which has a 20x20 cm2 sensitive area consisting of two crossed ribbons of 500 µm square scintillating fibers. The track position information is real-time extracted in an innovative way, using a reduced number of read-out channels to obtain a very large detection area but with moderate costs and complexity. The performance of the tracker has been investigated using s sources, cosmic rays, and a 62 MeV proton beam.

The prototype of the OFFSET (Optical Fiber Folded Scintillating Extended Tracker) tracker is presented. It exploits a novel system for particle tracking, designed to achieve real-time imaging, large detection areas, and a high spatial resolution especially suitable for use in medical diagnostics. The main results regarding the system architecture have been used as a demonstration of the technique which has been patented by the Istituto Nazionale di Fisica Nucleare (INFN). The prototype of this tracker, presented in this paper, has a 20 × 20 cm2 sensitive area, consisting of two crossed ribbons of 500 micron square scintillating fibers. The track position information is extracted in real time in an innovative way, using a reduced number of read-out channels to obtain very large detection area with moderate enough costs and complexity. The performance of the tracker was investigated using beta sources, cosmic rays, and a 62 MeV proton beam.

In this paper we describe a novel system for the tracking of charged particles, designed to achieve real-time imaging, large detection areas and high spatial resolution especially suitable for use in medical diagnostic. A prototype of this tracker, having a 20 × 20 cm2 sensitive area, consisting of two crossed ribbons of 500 11m square scintillating fibers has been developed. The track position information is extracted real time in an innovative way, using a reduced number of read-out channels to obtain very large detection area with enough moderate costs and complexity. The performances of the tracker have been investigated using both β sources and cosmic rays and finally with a 62 MeV proton beam.

One of the particular characteristics of diamond detectors is their fast charge collection time. This feature makes these detectors very attractive for timing measurements in both nuclear and particle physics experiments. The charge collection time in these detectors is of the order of a few hundred ps, therefore the timing performance depends greatly on the electronics readout of the detector. In this work we present comparative measurements made using a single crystal diamond detector and two different electronic readout chains. In particular, we used a charge sensitive amplifier (CSA) with a 100 MHz bandwidth and a voltage amplifier with a 2 GHz bandwidth. In order to evaluate the performance of the detector for charge signals generated by particles with energies below minimum ionizing, measurements were taken using 62 MeV proton beam at the INFN - Laboratori Nazionali del Sud. Another set of measurements was made with a 120 GeV proton beam at FNAL in order to evaluate the performance with MIP. The timing performance depends on the rise time of the signal and the Signal to Noise ratio. Both these characteristics are inversely related to the electronic readout bandwidth. The charge collection with the 62 MeV proton beam was about 130 Ke-. A SIN ratio of about 80 was obtained with the CSA, while the SIN ratio was approximately 4 with the 2 GHz broad-band amplifier. This resulted in a comparable time distribution value of around 70 ps RMS in both cases. However, charge collection is much smaller with minimum ionizing particles, and while it was possible to perform measurements with the CSA, with the broadband amplifier it was not possible to separate signals from the background noise. In this work we present and discuss the set-up used and the complete set of measurements, with final considerations regarding range of use to which these detector can be utilized.

Proton Computed Tomography (pCT) is an imaging method under investigation with the aim to improve the accuracy of treatment planning and patient positioning in hadron therapy. A pCT system should be capable to measure tissue electron density with an accuracy better than 1% and with a spatial resolution better than 1mm. A first apparatus based on a silicon tracker and a YAG:Ce crystal calorimeter, with a 5×5 cm2 active area, has been already developed by the authors in the framework of the PRIMA (Proton Imaging) collaboration and tested with proton beams with promising results. A second prototype with larger area (5×20 cm2) and improved data acquisition system is being designed. The details about this new prototype will be presented in this work.