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The search for neutrinoless double-beta (0νββ) decay is currently a key topic in physics, due to its possible wide implications for nuclear physics, particle physics, and cosmology. The NUMEN project aims to provide experimental information on the nuclear matrix elements (NMEs) that are involved in the expression of 0νββ decay half-life by measuring the cross section of nuclear double-charge exchange (DCE) reactions. NUMEN has already demonstrated the feasibility of measuring these tiny cross sections for some nuclei of interest for the 0νββ using the superconducting cyclotron (CS) and the MAGNEX spectrometer at the Laboratori Nazionali del Sud (LNS.) Catania, Italy. However, since the DCE cross sections are very small and need to be measured with high sensitivity, the systematic exploration of all nuclei of interest requires major upgrade of the facility. R&amp, D for technological tools has been completed. The realization of new radiation-tolerant detectors capable of sustaining high rates while preserving the requested resolution and sensitivity is underway, as well as the upgrade of the CS to deliver beams of higher intensity. Strategies to carry out DCE cross-section measurements with high-intensity beams were developed in order to achieve the challenging sensitivity requested to provide experimental constraints to 0νββ NMEs.

Radiochromic film dosimetry has been widely employed in most of the applications of radiation physics for over twenty years. This is due to a number of appealing features of radiochromic films, such as reliability, accuracy, ease of use and cost. However, current radiochromic film reading techniques, based on the use of commercial densitometers and scanners, provide values of dose only after the exposure of the films to radiation. In this work, an innovative methodology for the real-time reading of radiochromic films is proposed for some specific applications. The new methodology is based on opto-electronic instrumentation that makes use of an optical fiber probe for the determination of optical changes of the films induced by radiation and allows measurements of dose with high degree of precision and accuracy. Furthermore, it has been demonstrated that the dynamic range of some kinds of films, such as the EBT3 Gafchromic films (intensively used in medical physics), can be extended by more than one order of magnitude. Owing to the numerous advantages with respect to the commonly used reading techniques, a National Patent was filed in January 2018.

We report on a innovative Lab on Fiber (LOF) dosimeter for ionizing radiation monitoring at ultra-high doses. The new dosimeter consists in a metallo-dielectric resonator at sub-wavelength scale supporting localized surface plasmon resonances realized on the optical fiber (OF) tip. The resonating structure involves two gold gratings separated by a templated dielectric layer of poly(methyl methacrylate) (PMMA). Two LOF prototypes have been manufactured and exposed, at the IRRAD Proton Facility at CERN in Geneva, to 23 GeV protons for a total fluence of 0.67x10(16) protons/cm(2), corresponding to an absorbed dose of 1.8 MGy. Experimental data demonstrate the "radiation resistance" feature of the LOF devices and a clear dependence of the reflected spectrum on the total dose, expressed by a cumulative blue-shift of similar to 1.4 nm of the resonance combined with a slight increase of 0.16 dBm in the reflected spectrum. According to the numerical analysis and the literature, the main phenomenon induced by exposure to proton beam and able to explain the measured spectral behavior is the reduction of the PMMA thickness. Preliminary results demonstrated the potentiality of the proposed platform as dosimeter at MGy dose levels for High Energy Physics (HEP) experiments.

The present invention relates to a method and a system for real-time determination of characteristics of radio-chromic films, which is based on optical-fiber technology and allows determining the characteristics through real-time reading and from a remote location.

Commercial-off-the-shelf system-on-chip field-programmable gate arrays (FPGAs) are gaining momentum in space applications and their radiation characterization becomes crucial. This paper targets a cost-effective test setup and procedures for total ionization dose testing of miniaturized complex devices. We combine hardware and software techniques to perform on-chip irradiation via a 90Sr/90Y electron source and assess in detail the degradation of complex SRAM FPGAs. Our methodology combines multiple sensing mechanisms with correlation analysis to facilitate modeling of effects and tuning of a custom ring-oscillator network for future autonomous in-flight use. Focusing on 28-nm Zynq7000 devices, our results show Mrad total ionizing dose tolerance with parameters’ degradation in the area of 5%, zero functional errors, and nonuniform spatial response.

For the first time the Rutherford Back-Scattering Spectroscopy (RBS) technique has been successfully exploited for the measurement of the energy of a proton beam accelerated by the IBA Cyclone 18/18 medical cyclotron in operation at the Bern University Hospital. This accelerator, routinely used for radioisotope production for Positron Emission Tomography (PET) imaging is equipped with an external beam line devoted to research activities in several fields such as detector physics, medical applications of particle physics, accelerator physics. Recently a widespread request has raised for the availability of well characterized proton and neutron beams, particularly for radiation hardness studies and the development of new neutron detectors. A feasibility study for a future upgrade of the Bern cyclotron towards a neutron facility was started, which requires a complete and precise characterization of the proton beam. Along this line, the measurement of fundamental parameters of the primary proton beam, such as the maximum proton energy and its spread have been performed by means of the RBS technique with two different targets, namely gold and graphite foils.

A new methodology for Total Ionizing Dose (TID) tests is proposed. It is based on the employment of an on-chip 90Sr/90Y beta source as alternative to standard methods such as 60Co gamma rays and electrons from LINAC. The use of a compact beta source for TID tests has several advantages. In particular, the irradiation of devices with more than one radiation source results in a better representation of the complex space radiation environment composed of several types, energies and dose-rates. In addition, the use of an easy handling beta source allows the irradiation of electronic devices without any damage to other auxiliary circuit. In this work, 90Sr/90Y beta source dosimetry and related radiation field characteristics are discussed in depth. In order to validate the proposed source for TID tests, a rather complex device such as the “SPC56EL70L5” microcontroller from ST-Microelectronics was exposed to 90Sr/90Y beta rays. The results of this test were compared to that of a previous test of another sample from the same lot with a standard gamma 60Co source. The electronic performances following the two irradiations have been found to be in excellent agreement, by demonstrating therefore the validity of the proposed beta source for TID tests.

Experiments of nuclear physics have been carried out at the Bern medical cyclotron, in which a beam line dedicated to research activities is available. Our main goal is to upgrade this facility as a well-characterized neutron source for studies of radiation hardness and for tests of new neutron detectors. To achieve this result, preliminary measurements have been carried out among which the measurement of the incident proton energy by means of a method based on Rutherford backscattering spectroscopy. The analysis of the energy spectrum corresponding to protons elastically and inelastically backscattered by the carbon target allowed the precise identification of the excited states of 12C, including the Hoyle state. These results confirmed the Bern medical cyclotron as a reliable facility to perform research activities in the field of fundamental nuclear physics as well as of applied physics.

Recent results in the field of film dosimetry demonstrated that the Green–Saunders equation, a solution of the logistic equation describing phenomena of kinetics of chemical reactions, is the absolute calibration function for all radiochromic film types. Taking advantage of the new opto-electronics-based radiochromic film reading method, which allows real-time measurements of the spectral response of radiochromic films, we confirm that the film darkening is ruled by the Green–Saunders equation independently both from the reading instrument or the choice of the observable used for the calibration. In order to demonstrate it, we exposed an XR-QA2 Gafchromic film to 90Sr/90Y beta rays up to 1400 mGy. Film spectra are recorded in real-time. The calibration is performed by means of two analytic methods: evaluation of the integral under the curves from 500 nm to 645 nm and evaluation of the intensity at 570, 600 and 643 nm. Experimental data fit to the Green–Saunders equation for both methods.

The tolerance to the cumulative effects of ionizing radiation is one of the most important parameters to keep into account when selecting an EEE component for space applications. TID sensitivity is normally investigated measuring changes induced by gamma rays from 60Co sources to nominal parameters of a component or to its expected functional behavior. In this work we propose an on-chip 90Sr/90Y electron source as an alternative methodology for TID tests.60Co and 90Sr/90Y TID test setups for a complex SoC are compared in terms of complexity and of experimental results, investigating the use of a 90Sr/90Y as well as the established 60Co. We show that 90Sr allows a simpler test setup, manages to reproduce specific modes of failure obtained with 60Co and causes failures at comparable total doses. This makes 90Sr an interesting alternative to 60Co qualification and the use of untested components, to be further investigated especially for complex COTS SoCs.

In this work, we report on a novel approach for measuring the dose absorbed by the EBT3 Gafchromic™ films exposed to 1 MeV electron beam and 250 kV X-rays in the range 0.5–100 Gy. Although EBT3 is specifically designed to obtain best performance for applications where the maximum dose is less than 10 Gy, there are certain clinical applications requiring dose ranges well above this value. In order to cover wider dose ranges, further models characterized by a thinner sensitive layer and/or different chemical composition have been released. Another method exploiting the three-channel flatbed scanner to delay the saturation point of EBT3 has been also reported. The technique proposed here, aimed at extending the sensitivity of the EBT3 film to high doses up to 100 Gy while ensuring a low dose uncertainty, is based on a broadband analysis of the absorption spectrum of the film in response to irradiation. By combining a wavelength-based approach with the monitoring of two characteristic peaks of the EBT3 absorption spectrum, we demonstrated the capability of measuring the dose in the range 0.5–100 Gy with an experimental uncertainty below 4% for doses lower than 5.52 Gy and below 2% for higher dose levels. Finally, through a dynamic fitting procedure integrating the two aforesaid approaches, a total uncertainty lower than 4%, including both the experimental and fitting errors, was achieved in the whole range 0.5–100 Gy. These results are promising in view of a potential application of this technique in the field of clinical dosimetry at high dose levels.

The use of System-on-Chip (SoC) solutions in the design of on-board data handling systems is an important step towards further miniaturization in space. However, the Total Ionizing Dose (TID) and Single Event Effects (SEE) characterization of these complex devices present new challenges that are either not fully addressed by current testing guidelines or may result in expensive, cumbersome test configurations. In this paper we report the test setups, procedures and results for TID testing of a SoC microcontroller both using standard C 60 o and low-energy protons beams. This paper specifically points out the differences in the test methodology and in the challenges between TID testing with proton beam and with the conventional gamma ray irradiation. New test setup and procedures are proposed which are capable of emulating typical mission conditions (clock, bias, software, reprogramming, etc.) while keeping the test setup as simple as possible at the same time.

In this work, we report on the first demonstration of Lab on Fiber (LOF) dosimeter for ionizing radiation monitoring at ultra-high doses. The new dosimeter consists in a metallo-dielectric resonator at sub-wavelength scale supporting localized surface plasmon resonances realized on the optical fiber (OF) tip. The resonating structure involves two gold gratings separated by a templated dielectric layer of poly(methyl methacrylate) (PMMA). Two LOF prototypes have been manufactured and exposed at the IRRAD Proton Facility at CERN in Geneva to 23 GeV protons for a total fluence of 0.67 × 1016 protons/cm2, corresponding to an absorbed dose of 1.8 MGy. Experimental data demonstrated the “radiation resistance” feature of the LOF devices and a clear dependence of the reflected spectrum versus the total dose, expressed by a cumulative blue-shift of ~1.4 nm of the resonance combined with a slight increase of 0.16 dBm in the reflected spectrum. The numerical analysis carried out to correlate the experimental results with the dimensional and physical properties of the resonator, expected to be tightly connected to the absorbed dose, suggests that the main phenomenon induced by exposure to proton beam and able to explain the measured spectral behavior is the reduction of the PMMA thickness, which is also consistent with past literature in the field. Preliminary results demonstrated the potentiality of the proposed platform as dosimeter at MGy dose levels for high energy physics experiments.

Single-photon avalanche diodes (SPADs) in the CMOS technology are very attractive solution for photon detection due to the excellent timing resolution achievable. Unfortunately, such devices suffer from large values of the dark count (DC) pedestals. In this paper, we analyzed a test chip containing SPADs with different layouts, implemented in the 150-nm CMOS technology. The behavior of such devices has been investigated after proton irradiation. It is observed that, after irradiation, the DC rate switches between two or more discrete levels, phenomenon known as random telegraph signal (RTS). The effect is related to the density and distribution of defects in the semiconductor lattice. RTS characteristics have been studied as the function of both temperature and bias voltage. Discussion of results and main hypotheses on defect types responsible for RTS are reported.

We have newly developed a Hybrid Photo-Detector (HPD) with 2-inch diameter. It consists of a bialkali photocathode and a 3 mm x 3 mm Multi-Pixel-Photon Counter (MPPC) sealed in a glass tube. The electric field inside the tube is designed so that photoelectrons emitted from the photocathode are collected in the MPPC, where photoelectrons are amplified. For conventional HPDs with an avalanche diode , extremely high voltage such as -8kV has to be provided to achieve gain sufficient for single photon detection. However, our HPD with MPPC has single photon sensitivity only with lower voltage like PMTs due to high gain of MPPC. In addition, this device can cover larger area with only one MPPC. These features enable us to easily handle high performance HPD in various applications, such as high energy physics, biomedical field etc. This test sample was produced in 2016, and we have checked its basic characteristics. The peak photocathode quantum efficiency was found to be very high of 37% at the wavelength of 340 nm. We have confirmed that HPD with MPPC has capability of single photon detection in low operation voltage less than -2 kV. This report will present detailed performance studies of this sample.

Radiochromic film dosimetry is a technique particularly suitable for dose measurements of radiation hardness assurance tests. The main characteristics of radiochromic films are the precise, accurate and permanent dose values, ease of handling and data analysis, high spatial resolution and wide range of dose. However, measurements of the trend of the dose in time with radiochromic films are very difficult by means of commercial read-out tools. In this work we propose a new method, for which a National Patent was filed, for the determination of the dose in real-time and by remote control with radiochromic films. This method based on optoelectronic instrumentation, makes radiochromic film dosimetry an ideal technique for radiation hardness quality assurance tests.

The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design for a hybrid photodetector. The idea, born with the purpose to use a SiPM for large detection volumes, consists in replacing the classical dynode chain with a special SiPM. In this configuration, we match the large sensitive area of a photocathode with the performances of the SiPM technology, which therefore acts like an electron detector and so like a current amplifier. The excellent photon counting capability, fast response, low power consumption and the stability are among the most attractive features of the VSiPMT.We now present the progress on the realization of a 1-in. prototype and the preliminary tests we are performing on it. © 2017 Elsevier B.V.

Selected experiments in fundamental physics have been proposed for many years at the Tandem Accelerator of the University of Napoli 'Federico II's Department of Physics as a part of a one-semester laboratory course for graduate students. The aim of this paper is to highlight the educational value of the experimental realization of the nuclear reaction 19F(p,α)16O. With the purpose of verifying the mass–energy equivalence principle, different aspects of both classical and modern physics can be investigated, e.g. conservation laws, atomic models, nuclear physics applications to compositional analysis, nuclear cross-section, Q-value and nuclear spectroscopic analysis.

The continuous beam provided by the TTT-3 accelerator of the University of Naples have to be pulsed with 5 ns length bunch to allow experiments in many fields of the fundamental and applied physics. The characteristics of the first low energy chopper prototype and the results obtained during preliminary test with the beam are presented.

Projects attempting the direct detection of WIMP dark matter share the common problem of eliminating sources of background or using techniques to distinguish background events from true signals. Although experiments such as DarkSide have achieved essentially background free exposures through careful choice of materials and application of efficient veto techniques, there will still be a high burden of proof to convince the greater scientific community when a discovery is claimed. A directional signature in the data would provide extremely strong evidence to distinguish a true WIMP signal from that of an isotropic background. Two-phase argon time projection chambers (TPCs) provide an experimental apparatus which can both be scaled to the ton-scale size required to accommodate the low cross-section expected for WIMP interactions and have an anisotropy that could be exploited to evaluate the polar angles of the resulting nuclear recoils from WIMP collisions with target nuclei. Our studies show that even a modest resolution in the polar angle reconstruction would offer a powerful tool to detect a directional signature. In this contribution, the status of the ReD experiment, which is under construction at Naples University, will be also shown. The aim of the project is to assess and enhance the directionality of two-phase argon TPCs. ReD will use a small TPC exposed to a beam of mono-energetic neutrons to study the so called “columnar recombination” in liquid argon. This development could have high impact on the future experiments in the field, opening up the potential to find conclusive evidence for dark matter or disprove the WIMP hypothesis at and above the mass range explored by planned accelerator experiments.

A unique calibration equation for all radiochromic film types is proposed. The determination of this equation comes from an analogy that the authors made between the radiochromic and photographic processes. Photography dynamics is ruled by a differential equation, the logistic equation, describing phenomena of growth versus competition. A solution of the logistic equation is the Green-Saunders equation which was used for the first time by the same authors in a previous referred work for the calibration of a set of EBT3 Gafchromic films. Since this equation has a fundamental physical interpretation, the fitting parameters also represent important physical quantities and two of them in particular fix the film dynamics; one being the contrast and the other the abscissa of the inflection point of the sensitometric curve. In order to show the validity of this approach for more than one radiochromic film type, two sets of radiochromic films, the B3 and HD-V2 Gafchromic films were exposed to several known doses and the Green-Saunders equation was found to perfectly fit the experimental data. A comparison with the same procedure used for EBT3 Gafchromic films is proposed. The findings of this work are an important step forward in the understanding of an interesting and widely used dosimetry technique.

The characteristics of radiochromic films such as the direct visualization of radiation field, ease of use and data analysis are suited for the dosimetry monitoring in tests of radiation hardness space applications. In particular, in this work, in order to study the dependence of radiation type, energy and dose rate, as well as the dynamic range of EBT3 Gafchromic films, a set of films was exposed to radiation sources used in total ionizing dose (60Co gamma- and 90Sr/90Y beta-rays). The results have been found to be particularly suited for the employment of this kind of films in radiation hardness assurance tests.

Neutron beams have been produced at Laboratory of High Energy Physics (LHEP) of University of Bern. LEHP is equipped with an 18 MeV cyclotron with an external beam line. Simulations, analytical calculations and kinematics studies have been carried out, in order to produce several neutron beam configurations with characteristics suited for specific applications. Furthermore, a procedure for energy modulation has been developed to match the fixed cyclotron energy to the needed requirements. The technique described in this work is of general application and can be applied to more intense beams up to 1010 pps.

For the study of astrophysically relevant capture reactions in the underground laboratory LUNA a newsetup of high sensitivity has been implemented. The setup includes a windowless gas target, a 4p BGO summing crystal, and beam calorimeters. The setup has been recently used to measure the d(p,g) 3 He cross-section for the first time within its solar Gamowpeak, i.e. dow n to 2.5 keV c.m. energy. The features of the optimized setup are described. r 2002 Elsevier Science B.V. All rights reserved.

The VSiPMT (Vacuum Silicon Photomultiplier Tube) is an innovative design for a revolutionary hybrid photodetector. The idea consists in replacing the classic dynode chain of a classic PMT with a SiPM. This new device aims at extending SiPM technology to large detection volumes. In this configuration, we match the large sensitive area of a photocathode with the performance of SiPM technology, which thererefore acts like an electron detector and current amplifier. The excellent photon counting capability, fast response, low power consumption and great stability are among the most attractive features of the VSiPMT. Hamamatsu realized two VSiPMT industrial prototypes with a photocathode of 3 mm diameter. In this work we present the progresses on the realization of a 1-inch prototype based on CsI photocathode and the preliminary tests we are performing on it.

Beyond their important economic role in commercial communications, satellites in general are critical infrastructure because of the services they provide. In addition to satellites providing information which facilitates a better understanding of the space environment and improved performance of physics experiments, satellite observations are also used to actively monitor weather, geological processes, agricultural development and the evolution of natural and man-made hazards. Defence agencies depend on satellite services for communication in remote locations, as well as for reconnaissance and intelligence. Both commercial and government users rely on communication satellites to provide communication in the event of a disaster that damages ground-based communication systems, provide news, education and entertainment to remote areas and connect global businesses. The space radiation environment is an hazard to most satellite missions and can lead to extremely difficult operating conditions for all of the equipment travelling in space. Here, we first provide an overview of the main components of space radiation environment, followed by a description of the basic mechanism of the interaction of radiation with matter. This is followed by an introduction to the space radiation hardness assurance problem and the main effects of natural radiation to the microelectronics (total ionizing dose, displacement damage and the single-event effect and a description of how different effects occurring in the space can be tested in on-ground experiments by using particle accelerators and radiation sources. We also discuss standards and the recommended procedures to obtain reliable results.

The absolute cross section σ ( E ) for the radiative capture reaction 7 Be(p, γ ) 8 B at the center-of-mass energies E =0.32 to 2.61 MeV has been measured using a 7 Be target deposited on a Cu backing and observing the β -delayed α -particles from 8 B. The backing causes a loss of less than 1% of the 8 B residual nuclides. The resulting astrophysical S ( E ) factor at zero energy, S (0)=18.4±1.6 eV b, is consistent only with a restricted data set from previous work.

This paper discusses radiation tests on complex System-on-Chip (SoC) controllers using Low-Energy Protons (LEPs). The aim of this novel set of guidelines is to be also applicable to System In Package (SIP) or hybrid components that are now often used to overcome printed circuit board's real estate restrictions in Hi-Rel electronics.

This paper presents an intended test setup and methodology for testing micro-controller SoCs against the effects of ionizing radiations. The method structure is based on a modular test sequence for test definition, coding, validation and setup. It will be illustrated by the relevant example of a microcontroller solution including lockstep options. Our methodology proposes using low-energy protons for irradiation, and this paper compares this approach with current techniques, showing how proton testing is becoming increasingly interesting, especially for ultra-deep submicron processes in proton dominated environments like low-shielded Low Earth Orbit missions or aircraft avionics. Beyond the convenience of a simplified test setup one of the main advantages of the proton irradiation approach is that it can be used for simultaneous Single Event Effects (SEE) and Total Ionizing Dose (TID) characterization, closer to the "test as you fly" approach.

The indirect effect of oxygen background gas on the La/Al ratio during the growth of LaAlO3 (LAO) films by pulsed laser deposition (PLD) is analyzed, in a pressure range between 10^-3 and 10^-1 mbar. We resort to two complementary investigation methods: Rutherford backscattering spectroscopy and spectrally resolved, time-gated imaging of the laser plume. The first technique allows us to analyze the stoichiometry of the deposited films, and the latter allows us to analyze the plume expansion phase of the PLD process by collecting chemically resolved two-dimensional images of the relevant atomic/molecular species. The comparison between the results obtained by the two techniques allows us to highlight the role of the plume-gas interaction in affecting cations stoichiometry. Our results indicate that, in the considered pressure range, the background oxygen pressure affects the cations stoichiometry of the LAO films, besides determining their oxygen content.

Photon detection is a key factor to study many physical processes in several areas of fundamental physics research. Focusing the attention on photodetectors for particle astrophysics, the future experiments aimed at the study of very high-energy or extremely rare phenomena (e.g. dark matter, proton decay, neutrinos from astrophysical sources) will require additional improvements in linearity, gain, quantum efficiency and single photon counting capability. To meet the requirements of these class of experiments, we propose a new design for a modern hybrid photodetector: the VSiPMT (Vacuum Silicon PhotoMultiplier Tube). The idea is to replace the classical dynode chain of a PMT with a SiPM, which therefore acts as an electron detector and amplifier. The aim is to match the large sensitive area of a photocathode with the performances of the SiPM technology.

An excitation function of the ground-state gamma (0)-ray capture transition in C-12(alpha, gamma)O-16 at theta (gamma) = 90 degrees was obtained in far geometry using six Ge detectors, where the study of the reaction was initiated in inverse kinematics involving a windowless gas target. The detectors observed predominantly the El capture amplitude. The data at E = 1.32 to 2.99 MeV lead to an extrapolated astrophysical S factor S-E1(E-0) = 90 +/- 15 keV b at E-0 = 0.3 MeV (for the case of constructive interference between the two lowest E1 sources), in good agreement with previous works. However, a novel Monte Carlo approach in the data extrapolation reveals systematic differences between the various data sets such that a combined analysis of all available data sets could produce a biased estimate of the S-E1(E-0) value. As a consequence, the case of destructive interference between the two lowest E1 sources with S-E1(E-0) = 8 +/- 3 keV b cannot be ruled out rigorously.

The El amplitude of the transition to the ground state in the C-12(alpha, gamma)O-16 capture reaction was measured in the energy range E-cm=1.3 to 3.0 MeV using an intense C-12 beam in combination with a windowless He-4 gas target and an array of six 70% HPGe detectors. The detectors were placed in a ring-shaped geometry around the target at a distance of 17 cm on a plane perpendicular to the beam axis. A target length of 5.3 cm was defined by a 12.5 cm thick lead shielding. Passive and active shielding was used to achieve the necessary suppression of the beam induced and cosmic background. The results of this measurement and their extrapolation to the relevant energy during the helium burning phase in massive stars are reported.

For improved measurements of the key astrophysical reaction C-12(alpha, gamma)O-16 in inverted kinematics, a recoil separator ERNA is being developed at the 4 MV Dynamitron tandem accelerator in Bochum to detect directly the O-16 recoils with about 50% efficiency. Calculations of the ion beam optics including all filtering and focusing elements of ERNA are presented. Since the C-12 projectiles and the O-16 recoils have essentially the same momentum, and since the C-12 ion beam emerging from the accelerator passes through a momentum filter (analysing magnet), the C-12 ion beam must be as free as possible from O-16 contamination for ERNA to succeed. In the present work, the O-16 contamination was reduced from a level of 1 x 10(-11) to a level below 2 x 10(-29) by the installation of Wien filters both before and after the analysing magnet. The measurement of these and other beam specifications involved other parts of the final ERNA layout - sequentially a Wien filter, a 60 degrees dipole magnet, another Wien filter, and a Delta E-E telescope. The setup led to a measured suppression factor of 5 x 10(-18) for the C-12 ion beam. The experiments also indicate that an almost free choice of the charge state for the O-16 recoils is possible in the separator.

The energy spectra of the γ-rays emitted in the 35Cl + 92Mo reaction at incident energy E = 260 MeV were measured in coincidence with the ejectiles produced in dissipative reaction events. The cumulative energy spectrum of the γ-rays coming from the decay of the ejectiles was calculated within the statistical model and its comparison to the experimental spectrum evidences an excess in the data for Eγ = 8 to 12 MeV. Such an excess, fitted with a Lorentz curve, is attributed to the preequilibrium GDR γ-decay of the intermediate dinuclear system. The centroid energy of the Lorentz curve corresponds to a dipole oscillation along the symmetry axis of the system and its width is found to be comparable to that of the ground state GDR low energy component of the deformed dinucleus. The small quantal dispersion Δl = (10.3 ± 0.1)ħ of the entrance channel angular momentum, determined by analysing the dissipative fragment angular distribution in the framework of the Strutinsky model, is suggested to limit the broadening of the preequilibrium GDR width.

The recoil separator ERNA (European Recoil Separator for Nuclear Astrophysics) for improved measurements of the astrophysical key reaction C-12(alpha, gamma)O-16 is being developed at the 4 MV Dynamitron tandem accelerator in Bochum to detect directly the O-16 recoils. The total detection efficiency of about 50 % allows direct measurements in a much wider energy range than previously accessible. In addition this technique allows improved measurements not hampered by cosmic background problems when compared to gamma -ray detection.

The absolute cross section sigma(E) of the radiative capture reaction p(Be-7,gamma)B-8 at the center-of mass energy E = 992 keV has been measured using a radioactive 7Be ion beam and a windowless gas target system filled with H-2 gas. The B-8 residual nuclides were detected with a recoil separator consisting of momentum and velocity filters and a BE E detector telescope. The B-8 yield was observed concurrently with the Be-7+p elastic scattering yield, relating sigma(E) to the Rutherford scattering cross section. The resulting value, sigma(E) = 0.41+/-0.11 mu b, leads to an S(E) factor at zero energy of S(0) = 16+/-4 eV b, in fair agreement with recommended values.

The composition of particulate matter in the atmosphere of four major Italian towns (Florence, Genoa, Milan and Naples) has been studied with the extensive application of IBA techniques. The aerosol has been collected simultaneously in the four towns during the first weeks of year 2001, by two-stage continuous streaker samplers, which provide the separation of the particulate matter in two fractions. The concentrations in air of about 20 elements, and the total particulate mass, have been extracted in the PM2.5 and PM10 fractions with hourly resolution by PIXE, PIGE and optical analyses of about 2700 samples. IBA analyses have been performed at the 3 MeV external proton beam of the INFN accelerator facility at the University of Florence.

Radiochromic films are a commercial product available in a large number of different types. They can be used in a wide range of doses and fluence for different radiation types. The application in different fields such as photon and ion radiotherapy, industrial irradiations for modification of materials, sterilization and radiation hardness, makes very interesting to study the response of the films to more radiation types and energies. The aim of this work is to define the characteristics and dynamic range of EBT3 Gafchromic films for some specific applications. To this end the behaviour of EBT3 Gafchromic films has been studied in depth by comparing the films response to different radiation types. In particular, this work has been carried out to establish a useful procedure to monitor the electronic device's irradiations for radiation hardness applications. The dynamic range of EBT3 films has been found to be compatible with the typically demanded fluences and the calibration has been found to be absolute, namely independent of the incident radiation type. The easy handling, the possibility of replacement of the films and high resolution power allow the monitoring of irradiations with a high range of doses.

We worked on the R&D of an innovative photodetector, the Vacuum Silicon Photomultiplier Tube (VSiPMT). The VSiPMT is composed by a photocathode and a solid state amplification stage. A semi-transparent conductive layer is necessary to supply voltage and to obtain a highly efficient CsI photocathode. Since the literature is poor on this topic we performed a systematic and detailed study of a set of semi-transparent conductive layers, made by different material and thickness. A CsI photocathode was evaporated on each sample. The impact of the semi-transparent conductive layer on the quantum efficiency of the photocathode is discussed.

The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design for a revolutionary hybrid photodetector. The idea, born with the purpose to use a SiPM for large detection volumes, consists in replacing the classical dynode chain with a SiPM. In this configuration, we match the large sensitive area of a photocathode with the performances of the SiPM technology, which therefore acts like an electron detector and so like a current amplifier. The excellent photon counting capability, fast response, low power consumption and great stability are among the most attractive features of the VSiPMT. In order to realize such a device we first studied the feasibility of this detector both from theoretical and experimental point of view, by implementing a Geant4-based simulation and studying the response of a special non-windowed MPPC by Hamamatsu with an electron beam. Thanks to this result Hamamatsu realized two VSiPMT industrial prototypes with a photocathode of 3mm diameter. We present the progress on the realization of a 1-inch prototype and the preliminary tests we are performing on it.

Nowadays we live in the so-called "Silicon Era", in which devices based on the silicon technology permeate all aspects of our daily life. One can simply think how much silicon is in the everyday household objects, gadgets and appliances. The impact of silicon technology has been very relevant in photodetection as well. it enables designing large or very large-scale integration devices, in particular microchips and pixelled detectors like the Silicon Photo Multiplier made of micrometric channels grouped in mm(2) pixels. However, on the horizon, the recent development of nanotechnologies is opening a new direction in the design of sub-micron photodevices, owing to the capability to deal with individual molecules of compounds or to chemically grow various kinds of materials. Among them, carbon compounds appear to be the most promising materials being chemically very similar to silicon, abundant and easy to handle. In particular, carbon nanotubes (CNT) are a very intriguing new form of material, whose properties are being studied worldwide providing important results. The photoelectric effects observed on carbon nanotubes indicate the possibility to build photodetectors based on CNTs inducing many people to claim that we are at the beginning of a Post Silicon Era or of the Carbon Era. In this paper, we report on the most important achievements obtained on the application of nanotechnologies to photodetection and medical imaging, as well as to the development of radiation detectors for astro-particle physics experiments.

In a recent experiment performed in Naples by using the TTT-3 tandem accelerator, the 19F(p, α0) reaction has been investigated at low bombarding energies, Ep = 0.6–1 MeV. Excitation functions and angular distributions have been obtained by using several solid state detectors preceded by thin aluminium absorbers. By analysing angular distributions in terms of Legendre and cosine polynomials, a few spectroscopic ambiguities concerning the excited states of the compound nucleus, 20Ne, in the excitation energy region E* = 13.4–13.8 MeV, have been solved. Moreover, this reaction plays an important role for the description of the fluorine nucleosynthesis. For this reason, the astrophysical S-factor has also been extracted and the results have been compared with the literature data.

We report some recent experimental results on the spectroscopy of 13C and 20Ne nuclei by means of low energy nuclear reactions carried out with high resolution electrostatic accelerators. In the case of 13C we investigated the possible existence of a-cluster states above the a emission threshold by means of low energy elastic resonant scattering α+9Be in direct kinematics. Excitation functions show the presence of various resonances that have been reproduced by R-matrix fit. We studied also the structure of 20Ne by means of the 19F(p,α0) reaction at sub-barrier energies. The spectroscopy of 20Ne excited states in the region Ex 13.5-14.0 MeV can be probed by analyzing experimental angular distributions and excitation functions. This reaction plays an important role also in the CNOF cycle and is an important ingredient to describe hydrogen-induced destruction of fluorine in massive stars. For this reason we investigated the trend of S-factor, that has been compared with results previously reported in the literature. © Published under licence by IOP Publishing Ltd

The VSiPMT (Vacuum Silicon PhotoMultiplier Tube) is an innovative design we proposed for a revolutionary photon detector. The main idea is to replace the classical dynode chain of a PMT with a SiPM (G-APD), the latter acting as an electron detector and amplifier. The aim is to match the large sensitive area of a photocathode with the performance of the SiPM technology. The VSiPMT has many attractive features. In particular, a low power consumption and an excellent photon counting capability. To prove the feasibility of the idea we first tested the performance of a special non-windowed SiPM by Hamamatsu (MPPC) as electron detector and current amplifier. Thanks to this result Hamamatsu realized two VSiPMT industrial prototypes. In this work, we present the results of a full characterization of the VSiPMT prototype.

We invented (2007) the VSiPMT, a novel, high-gain, photo detector device and we publically proposed this idea in an International Conference for the first time at the 11th Topical Seminar on Innovative Particle and Radiation Detectors (IPRD08) in Siena, triggering deep discussions on the feasibility of the device itself and on the convenience of such a solution. After several years spent in designing, evaluation, tests and eventually negotiations with some suppliers, we finally got a couple of prototypes of the Vacuum Silicon Photo Multiplier Tube (VSiPMT) made under our specifications by Hamamatsu. We present in this paper the most important results of characterization tests of the first prototypes of the VSiPMT. © 2014 IOP Publishing Ltd and Sissa Medialab srl.

We give the LUNA results on the $\ensuremath{\sigma}(E)$ cross section measurement of a key reaction of the proton-proton chain strongly affecting the calculated neutrino luminosity from the Sun: ${}^{3}\mathrm{He}{(}^{3}\mathrm{He},2p{)}^{4}\mathrm{He}$. Because of the cosmic ray suppression provided by the Gran Sasso underground laboratory, it has been possible to measure $\ensuremath{\sigma}(E)$ throughout the energy range in which this reaction occurs in the Sun, i.e., down to $16.5\mathrm{keV}$ center of mass energy. The data clearly show the cross section increase due to the electron screening effect but they do not exhibit any evidence for a narrow resonance suggested to explain the ${}^{8}\mathrm{B}$ and ${}^{7}\mathrm{Be}$ solar neutrino flux reduction.