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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.

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.

A high energy resolution, high dispersive power Thomson Parabola Spectrometer has been developed at INFN-LNS in order to characterize laser-driven beams up to 30- 40 MeV for protons. This device has parallel electric and magnetic field to deflect particles of a certain charge-to-mass ratio onto parabolic traces on the detection plane. Calibration of the deflection sector is crucial for data analysis, namely energy determination of analysed beam, and to evaluate the effective energy limit and resolution. This work reports the study of monochromatic proton beams delivered by the TANDEM accelerator at LNS (Catania) in the energy range between 6 and 12.5 MeV analysed with our spectrometer which allows a precise characterization of the electric and magnetic deflections. Also the energy and the Q/A resolutions and the energy limits have been evaluated proposing a mathematical model that can be used for data analysis, for the experimental set up and for the device scalability for higher energy.

Laser accelerated proton beams represent nowadays an attractive alternative to the conventional ones and they have been proposed in different research fields. In particular, the interest has been focused in the possibility of replacing conventional accelerating machines with laser-based accelerators in order to develop a new concept of hadrontherapy facilities, which could result more compact and less expensive. With this background the ELIMED (ELIMED: ELI-Beamlines MEDical applications) research project has been launched by LNS-INFN researchers (Laboratori Nazionali del Sud-Istituto Nazionale di Fisica Nucleare, Catania, IT) and ASCR-FZU researchers (Academy of Sciences of the Czech Republic-Fyzikalni ustar, Prague, Cz), within the pan-European ELI-Beamlines facility framework. Its main purposes are the demonstration of future applications in hadrontherapy of optically accelerated protons and the realization of a laser-accelerated ion transport beamline for multidisciplinary applications. Several challenges, starting from laser-target interaction and beam transport development, up to dosimetric and radiobiological issues, need to be overcome in order to reach the final goals. The design and the realization of a preliminary beam handling and dosimetric system and of an advanced spectrometer for high energy (multi-MeV) laser-accelerated ion beams will be shortly presented in this work.

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.

Nowadays, laser-driven proton beams generated by the interaction of high power lasers with solid targets represent a fascinating attraction in the field of the new acceleration techniques. These beams can be potentially accelerated up to hundreds of MeV and, therefore, they can represent a promising opportunity for medical applications. Laser-accelerated proton beams typically show high flux (up to 1011 particles per bunch), very short temporal profile (ps), broad energy spectra and poor reproducibility. In order to overcome these limitations, these beams have be controlled and transported by means of a proper beam handling system. Furthermore, suitable dosimetric diagnostic systems must be developed and tested. In the framework of the ELIMED project, we started to design a dedicated beam transport line and we have developed a first prototype of a beam line key-element: an Energy Selector System (ESS). It is based on permanent dipoles, capable to control and select in energy laser-accelerated proton beams. Monte Carlo simulations and some preliminary experimental tests have been already performed to characterize the device. A calibration of the ESS system with a conventional proton beam will be performed in September at the LNS in Catania. Moreover, an experimental campaign with laser-driven proton beam at the Centre for Plasma Physics, Queens University in Belfast is already scheduled and will be completed within 2014.

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.

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.

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.

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.