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In this paper, we describe the work done in order to run the CT 3-D reconstruction algorithm on the 120 GB raw data from the more than 25\thinspace000 radiographs acquired from the Kongo Rikishi (XIII century) Japanese wooden statue. The work was done using the Microsoft (Redmond) HPC cluster and then on a local cluster at the INFN of Bologna. A speed-up factor of 75 was reached. [ABSTRACT FROM PUBLISHER]

This paper describes the beam flux monitoring system that has been developed at the Superconducting Cyclotron at INFN-LNS (Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali del Sud, Catania, Italy) in order to monitor the beam parameters such as energy, flux, beam profile, for SEE (Single Event Effects) cross-sections determination and DD (Displacement Damage) studies. In order to have an accurate and continuous monitoring of beam parameters we have developed fully automatic dosimetry setup to be used during SEE (with heavy ions) and DD (with protons up to 60 MeV) tests of electronic devices and systems. The final goal of our activity is to demonstrate that the operation of such a system in air is not detrimental to the accuracy on controlling the beam profile, energy and fluence delivered onto the DUT (Device Under Test) surface, even with non relativistic heavy ions. We have tested our beam monitoring system with the “Reference SEU monitor” developed by ESA/ESTEC, the results are discussed here. [ABSTRACT FROM PUBLISHER]

We report on the latest results from the development of 3-D silicon radiation detectors at Fondazione Bruno Kessler of Trento (FBK), Italy (formerly ITC-IRST). Building on the results obtained from previous devices (3-D Single-Type-Column), a new detector concept has been defined, namely 3-D-DDTC (Double- sided Double-Type Column), which involves columnar electrodes of both doping types, etched from alternate wafer sides, stopping a short distance (d) from the opposite surface. Simulations prove that, if d is kept small with respect to the wafer thickness, this approach can yield charge collection properties comparable to those of standard 3-D detectors, with the advantage of a simpler fabrication process. Two wafer layouts have been designed with reference to this technology, and two fabrication runs have been performed. Technological and design aspects are reported in this paper, along with simulation results and initial results from the characterization of detectors and test structures belonging to the first 3-D-DDTC batch. [ABSTRACT FROM AUTHOR]

Performance, reliability and scalability in data-access are key issues in the context of the computing Grid and High Energy Physics data processing and analysis applications, in particular considering the large data size and I/O load that a Large Hadron Collider data centre has to support. In this paper we present the technical details and the results of a large scale validation and performance measurement employing different data-access platforms-namely CASTOR, dCache, GPFS and Scalla/Xrootd. The tests have been performed at the CNAF Tier-1, the central computing facility of the Italian National Institute for Nuclear Research (INFN). Our storage back-end was based on Fibre Channel disk-servers organized in a Storage Area Network, being the disk-servers connected to the computing farm via Gigabit LAN. We used 24 disk-servers, 260 TB of raw-disk space and 280 worker nodes as computing clients, able to run concurrently up to about 1100 jobs. The aim of the test was to perform sequential and random read/write accesses to the data, as well as more realistic access patterns, in order to evaluate efficiency, availability, robustness and performance of the various data-access solutions. [ABSTRACT FROM PUBLISHER]

At the Department of Physics of the University of Pisa, Italy, a new and fully engineered version of the YAP-(S)PET small animal scanner has been recently installed. The new YAP-(S)PET is able to perform both PET and SPECT studies on small animals. The scanner is made up of four heads: each one is composed of a 4 × 4 cm² YAIO3:Ce (or YAP:Ce) matrix of 20 × 20 elements, 2 × 2 × 25 mm³ each, coupled to a Position Sensitive Photomultiplier (PS-PMT) (Hamamatsu R2486). The four modules are positioned on a rotating gantry. The switching to the SPECT modality is easily made by mounting a high resolution parallel hole (0.6 mm ⊘, 0.15 mm septum) lead collimator in front of each crystal. This paper reports the performance of the system in terms of absolute sensitivity and spatial resolution for both PET and SPECT modalities. The scatter fraction and noise-equivalent count rate (NEC) for a mouse phantom for different energy windows have been measured in PET modality. Images of phantoms and animals are also presented. [ABSTRACT FROM AUTHOR]

Gamma-ray large area space telescope (GLAST) is a next generation high-energy gamma-ray space observatory designed for observations of celestial gamma-ray sources in the energy band extending from 10 MeV to more than 100 GeV. The main instrument, the large area telescope (LAT), consists of a microstrip silicon tracker, a calorimeter, an anticoincidence detector, and the data acquisition (DAQ) system. This paper summarizes the results obtained during the radiation testing of the ASIC chips used in the LAT tracker. Both single event effects (SEE) and total ionizing dose effect (TID) tests have been performed, as part of the radiation hardness assurance (RHA) for the planned 5-yr mission. Heavy-ion SEE tests have been performed at the SIRAD irradiation facility at the INFN National Laboratories of Legnaro, Italy (LNL) and at the Texas A&M University (TAMU) Cyclotron Institute, with LET values ranging up to ∼80 MeV × cm²/mg. The tolerance of the chips to ionizing radiation has been evaluated with heavy ions and by irradiating chips with the spherical 60Co gamma source of the LNL CNR-ISOF laboratory. [ABSTRACT FROM AUTHOR]

This work is concerned with the effects of γ-rays on the static, signal and noise characteristics of JFET-based circuits belonging to a fabrication technology made available by the Istituto per la Ricerca Scientifica e Tecnologica (ITC-IRST), Trento, Italy. Such a process has been tuned with the aim of monolithically integrating the readout electronics on the same highly resistive substrate as multielectrode silicon detectors. The radiation tolerance of some test structures, including single devices and charge sensitive amplifiers, was studied in view of low-noise applications in industrial and medical imaging, X-and γ-ray astronomy and high energy physics experiments. This paper intends to fill the gap in the study of gamma radiation effects on JFET devices and circuits belonging to detector-compatible technologies. [ABSTRACT FROM AUTHOR]

The use of NE102A-BaF2 phoswich detector drastically improves the particle identification with respect to BaF2 crystals. To better exploit the possibility of light ion discrimination we have applied digital signal processing to the signals, on-beam collected with NE102A-BaF2 phoswich. We present the results obtained for the heavy ion charge identification (up to Z = 50) and light particle mass identification, using digital pulse shape acquisition and a 12-bit, 2 GSample/s sampling analog to digital converter. The results concerning the response of BaF2 -plastic phoswich to the reaction products issued at forward angles in the collision of 35.1 MeV/u 124Sn beam on 64Ni target have been obtained at the Superconducting Cyclotron of the Laboratori Nazionali del Sud in Catania. [ABSTRACT FROM AUTHOR]

A high performance detector head with matrices of silicon photomultipliers (SiPMs) as photodetectors is under development at the University of Pisa and INFN Pisa. The silicon photomultipliers fabricated at FBK-irst (Trento, Italy) are being evaluated for this purpose. Single SiPM detectors of 1 mm × 1 mm size and the first SiPM test matrices composed of four (2 × 2) pixel elements in a common substrate have been tested with LYSO crystals. The energy and timing resolution of single SiPMs have been evaluated, obtaining an energy resolution of 20% FWHM at 511 keV, and a coincidence timing resolution of 1.4 ns FWHM. In addition, the first tests performed with the SiPM matrices prove the feasibility of such devices. [ABSTRACT FROM AUTHOR]

A new multi-energy CT for small animals is operative (now only in scanning mode) at the Physics Department of the University of Bologna. The system makes use of a set of quasi-monochromatic X-ray beams produced by means of an Highly-Oriented Pyrolytic Graphite Bragg monochromator. This source is able to provide beams with energy tunable in a range from 20 to 70 keV. Here we present a complete characterization of the source. A theoretical model of the source has been analyzed, according to the known Zachariasen's theory for diffracting crystals [1]. The beams have also been characterized in resolution and intensity, over the accessible range, and we present here some measured spectra. The monochromator system demonstrated an energy spread of about 3 keV (Full Width at Half Maximum-FWHM) at a beam energy of 26 keV. At the same energy, the intensity of the output beam is about 6% of the primary beam. [ABSTRACT FROM AUTHOR]

Mobile-Dose has been designed for a very innovative use: the integration in a robotic machinery for automatic preparation of radioactive doses, to be injected to patients in Nuclear Medicine Departments, with real time measurement of the activity under preparation. Mobile-Dose gives a constant measurement of the dose during the filling of vials or syringes, triggering the end of the filling process based on a predefined dose limit. Several applications of Mobile-Dose have been delivered worldwide, from Italian hospitals and clinics to European and Japanese ones. The design of such an instrument and its integration in robotic machineries, was required by an Italian company specialised in radiation protection tools for nuclear applications, in the period 2001-2003. At the time of its design, apparently no commercial instruments with a suitable interfacing capability to the external world existed: we designed it in order to satisfy all the strict requirements coming from the medical aspects (precision within 10%, repeatability, stability, time response) and from the industrial conceiving principles that are mandatory to ensure a good reliability in such a complicated environment. The instrument is suitable to be used in standalone mode too, thanks to its portability and compactness and to the intelligent operator panel programmed for this purpose. [ABSTRACT FROM PUBLISHER]

LiF based thermoluminescent materials are the most used passive detectors in the field of radiation protection. For personal and area dosimetry in mixed neutron and photon fields, 6LiF and 7LiF TLD pairs are employed for the simultaneous determination of neutron and photon doses. Therefore, an accurate knowledge of their sensitivity to photons and thermal neutrons is essential. Aimed at providing reliable sensitivity data for new LiF based TL materials, an experimental study was performed in the framework of collaboration between INFN Frascati National Laboratories and ENEA, Italy. The 6LiF(Mg, Cu, P) material from TLD Poland, was specially manufactured in six versions with different sensitive thickness (t = 40, 60, 80, 100, 150 and 230 mg·cm-2), which implies different neutron and photon sensitivity. Together with the 7LiF(Mg, Cu, P) material, namely MCP-7, all seven type of TLDs were irradiated in reference beams of photons and thermal neutrons, at the calibration facilities of INFN and ENEA. The study provides a set of sensitivity data and discusses the performance of the investigated materials for the dosimetry of mixed neutron and photon fields. [ABSTRACT FROM AUTHOR]