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The Chiaravalle Cross, a masterpiece of Mediaeval goldsmithery, went under restoration in 2016. This was a unique opportunity to undertake an in-depth multidisciplinary study. Several issues were addressed, as for example the chronology of the Cross, lacking any official document about it. The scientific investigations included in situ and laboratory measurements, and the analyses, part of a multidisciplinary protocol, completely characterized the gemstones adorning the Cross, the cameos, the gold, silver, jasper and glass parts, to derive indications on their provenance, authenticity and dating issues. All the results were shared with the whole collaboration of experts, which included art historians, a restorer, a conservator, a scholar in ancient glyptic, gemologists, archaeometallurgists, physicists and scientists in a very fruitful exchange of knowledge. This work is an example of a real multidisciplinary research, gathering good practices in the study of a complex piece of art.

Within the frame of a collaboration among the Accademia Nazionale dei Lincei, XGLab-Bruker and ENEA, some of the Renaissance wall paintings decorating Villa Farnesina interiors have been investigated by macro-X-ray fluorescence (MAXRF). In this paper is presented and discussed a case study concerning some sketches discovered about 50years ago during the detachment of painted curtains. Results have brought to light a palimpsest whose discussion calls into question the attribution proposed when it has been discovered.

Unexpected finding of Egyptian blue emerged in Raphael’s fresco Triumph of Galatea at Villa Farnesina, in Rome. This pigment is the oldest man-made blue, dating back to Egyptians who manufactured it first and whose occurrence was thought to be lost with Romans. Thanks to advanced imaging techniques it has been possible to non-invasively map its distribution throughout the frescoed surface and to obtain a non-invasive imaging stratigraphic analysis indicating whether pure painting layers, mixtures or overlapping occurred. Egyptian blue identification on Raphael’s Galatea is so far the earliest of sixteenth century, and could be the first step towards its tracking in Renaissance, demonstrating that non-invasive techniques are a mandatory step not only for materials identification but also for understanding art history and its dynamics.

An acquisition campaign of macro-X-ray fluorescence scanning measurements on the vault of the Loggia of Cupid and Psyche, frescoed by Raphael and his workshop in the Villa Farnesina (Rome), supplied the occasion of testing the potentialities for such diagnostic tool/technique in studying wall paintings in situ. In this paper, the methodological approach is considered in depth, to highlight significant problematics deriving from nature of materials, painting technique and spatial peculiarities of this kind of artwork, as well as from the treatment and decoding of raw data. Data obtained through a single-spot XRF campaign, carried out during the past restorations of the Loggia, have been considered for comparisons. Graphical abstract: [Figure not available: see fulltext.]. © 2018, Accademia Nazionale dei Lincei.

In the recent years, an increasing interest has been devoted to the development of compact macro X-ray fluorescence (MA-XRF) systems, establishing the technique as one of the most powerful non-invasive method for the characterization of artworks. Nevertheless, important information may be lost due to the poor signal-to-noise ratio, which characterises spectra collected with a limited acquisition time. Moreover, well-known drawbacks of the XRF analysis, such as the matrix effect and the penetration depth of X-rays, have to be also considered. In the attempt to overcome such limitations, without compromising the potentialities of a MA-XRF imaging analysis in terms of dimension of investigated surface and time of analysis, a specific methodological strategy is proposed. In particular, high signal-to-noise ratio maps were acquired on regions of interest selected after preliminary fast scans on the entire painting. Subsequently, the elaboration of the dataset was supported by the use of ad hoc analytical tools, such as correlation diagrams, averaged extracted spectra and line emission maps for each element. The correct interpretation of the non-invasive results allowed to define a proper sampling strategy. The proposed experimental workflow has been applied to a masterpiece panel painting by Cimabue (1240–1302) depicting “Madonna Enthroned with the Child and Two Angels”, disclosing new knowledge on the adopted execution technique, about which little is known. Thus, for the first time a painting created by Cimabue was investigated under a material and technical point of view. Due to the relevance of the information obtained by MA-XRF analyses, micro-destructive investigations were carried out. Thus, the joint evaluation of elemental distribution and the stratigraphic composition of the selected samples allowed to obtain information about Cimabue painting technique. Particular attention was devoted to the characterization of the throne decorations, pointing out new questions on a non-conventional middle-age gilding technique that need still to be investigated.

We present a multi-analytical in situ non-invasive study of a series of emblematic paintings by Alessandro Milesi (1856-1945) from the collection of the International Gallery of Modern Art Ca' Pesaro in Venice. Eight paintings dated from 1897 to 1910 were studied with imaging and spectroscopic techniques. White pigments were characterized by a combination of X-ray fluorescence spectroscopy which traced the presence of zinc-based pigments in Milesi's paintings, Raman Spectroscopy, Laser Induced Fluorescence (LIF) Spectroscopy and Time-resolved Luminescence Imaging. Time-resolved analysis of luminescence emissions revealed the nanosecond emission from organic compounds and the slower emission from the luminescent inorganic pigment Zinc Oxide that varied between 1.1 and 1.6 microseconds. In this work, data regarding the distribution of luminescent pigments was acquired with a time-gated imaging detector. Furthermore, differences in emission decay kinetics recorded from different paintings can be ascribed to different paint formulations or origins of the Zinc white in paint.

This works presents the analysis of polychrome objects using transportable instrumentation for the analysis and characterisation of the palette of Ancient Egyptian Objects from a Late-period coffin in the Egyptian Museum in Cairo, with a focus both on practical details of measurements and specific results from imaging and point-like analyses. Multispectral imaging was combined with X-ray fluorescence, Raman and Photoluminescence spectroscopies. All instrumentation was transported to the museum and analysis was carried out in situ within the Conservation Laboratory. Results demonstrate the strength of imaging for mapping the presence of Egyptian Blue and mixtures of the pigment, while elemental and molecular analyses indicate the presence of mixtures of pigments to create greens, and the selective use of yellow earth or yellow ochre. In situ analysis informed sampling to determine the type of wood used and the stratigraphy of the multiple layers of white pigments and cloth used to create the ground on which the painting was executed.

Multi-element germanium detectors for X-ray fluorescence are widely used in synchrotron experiments and in particular in XAFS experiments. This paper presents the construction and characterization of a demonstrator built to investigate the viability of multi-element monolithic germanium detectors equipped with CMOS front-end electronics. Semikon Detector GmbH fabricated a germanium sensor segmented with a pad pattern with pad size $1\times 1~\hbox{mm}^2$ . 16 channels were instrumented with the CUBE preamplifiers developed at XGLab Srl. The detector was tested with radioactive sources and with the synchrotron X-ray beam of Diamond. The results showed spectra with energy resolution satisfactory for XAFS experiments but with a considerable tail. The low energy tail was proved to be due to charge sharing. In addition the spectra showed the peak stability as a function of counting rate better than 1% for rate up to 838 kcps. The non-linearity of the peak position vs. energy was estimated to be a maximum of 0.13% No evidence of charge loss in the crystal was identified. This work proved that this technology is a viable option to improve the throughput of germanium fluorescence detectors as long as methods to reduce events leading to charge sharing are in place.

SIDDHARTA collaboration performed the highest precision measurement of the shift and width of the kaonic hydrogen 1s state induced by the strong interaction at the DAΦNE collider of Laboratori Nazionali di Frascati. The result provides vital constraints on the theoretical description of the low-energy \({\bar{K} N}\) interactions.

The antikaon interaction on nucleons and nuclei in the low-energy regime is neither simple nor well understood. Rather direct access to this field is provided by x-ray spectroscopy of light kaonic atoms like kaonic hydrogen, deuterium and helium isotopes. A series of precision measurements on kaonic atoms was performed very successfully by the SIDDHARTA Collaboration at the DAΦNE electron-positron collider at LNF-INFN (Frascati, Italy). Consequently, new precision data on the strong interaction observables (i.e. energy shift and broadening of low-lying atomic states) were delivered having an important impact on the theory of low-energy QCD with strangeness. Presently, the follow-up experiment, SIDDHARTA-2, is in preparation, aiming at a determination of the strong interaction observables in kaonic deuterium as the highest priority; other type of measurements (light and heavier kaonic atoms) are as well foreseen. With the kaonic deuterium data the antikaon-nucleon isospin-resolved scattering lengths can be extracted for the first time. An overview of the progress and present status of experimental studies and an outlook to future perspectives in this fascinating research field is given.

The work proposes a versatile tool for closed-loop operation of MEMS gyroscopes at wafer level, as a mean both to improve existing characterization techniques, and as well to introduce innovative characterization features. These pages specifically address the need for fast measurements of drive-mode quality factors for gyroscopes at large volumes.

We propose a non-invasive approach for the study of illuminated manuscripts based on the combination of near-infrared reflectance imaging, X-ray fluorescence mapping, and Raman spectroscopy. Taking advantage of the different absorption coefficient of the characteristic X-ray emission lines of a specific element, we have implemented a differential mapping method to distinguish the X-ray emissions from two paint layers of a manuscript. This approach was applied to a coat-of-arms of a precious illuminated manuscript belonging to the Trivulziana library collection and revealed specific patterns through the mapping of the spatial distribution of lead in different paint layers. Multivariate methods, including principal component analysis and non-negative matrix factorization, applied to the X-ray fluorescence mapping dataset demonstrate the spatial correlation between different elements. The use of complementary Raman and X-ray fluorescence spectroscopy has hence permitted the identification of the pigments employed in the original and overpainting layers found on the coat-of-arms. Through analysis, it was possible to identify the patron of the Salterium, attributed to Fracesco del librai, as 15th C. bishop Bernardo de' Rossi. (C) 2015 Elsevier B.V. All rights reserved.

We propose a non-invasive approach for the identification and mapping of pigments in paintings. The method is based on three highly complementary imaging spectroscopy techniques, visible multispectral imaging, X-Ray fluorescence mapping and Raman mapping, combined with multivariate data analysis of multidimensional spectroscopic datasets for the extraction of key distribution information in a semi-automatic way. The proposed approach exploits a macro-Raman mapping device, capable of detecting Raman signals from non-perfectly planar surfaces without the need of refocusing. Here, we show that the presence of spatially correlated Raman signals, detected in adjacent points of a painted surface, reinforces the level of confidence for material identification with respect to single-point analysis, even in the presence of very weak and complex Raman signals. The new whole-mapping approach not only provides the identification of inorganic and organic pigments but also gives striking information on the spatial distribution of pigments employed in complex mixtures for achieving different hues. Moreover, we demonstrate how the synergic combination on three spectroscopic methods, characterized by highly different time consumption, yields maximum information.

Treatments delivered by proton therapy are affected by uncertainties on the range of the beam within the patient, requiring medical physicists to add safety margins on the penetration depth of the beam. To reduce these margins and deliver safer treatments, different projects are currently investigating real-time range control by imaging prompt gammas emitted along the proton tracks in the patient. This study reports on the feasibility, development and test of a new concept of prompt gamma camera using a slit collimator to obtain a one-dimensional projection of the beam path on a scintillation detector. This concept was optimized, using the Monte Carlo code MCNPX version 2.5.0, to select high energy photons correlated with the beam range and detect them with both high statistics and sufficient spatial resolution. To validate the Monte Carlo model, spectrometry measurements of secondary particles emitted by a PMMA target during proton irradiation at 160 MeV were realized. An excellent agreement with the simulations was observed when using subtraction methods to isolate the gammas in direct incidence. A first prototype slit camera using the HiCam gamma detector was consequently prepared and tested successfully at 100 and 160 MeV beam energies. Results confirmed the potential of this concept for real-time range monitoring with millimetre accuracy in pencil beam scanning mode for typical clinical conditions. If we neglect electronic dead times and rejection of detected events, the current solution with its collimator at 15 cm from the beam axis can achieve a 1-2 mm standard deviation on range estimation in a homogeneous PMMA target for numbers of protons that correspond to doses in water at the Bragg peak as low as 15 cGy at 100 MeV and 25 cGy at 160 MeV assuming pencil beams with a Gaussian profile of 5 mm sigma at target entrance.

Summary 1. Spatially resolved X-ray fluorescence (XRF) spectroscopy with synchrotron radiation is a technique that allows imaging and quantification of chemical elements in biological specimens with high sensitivity. In the present study, we applied XRF techniques at a macro and micro level to carry out drug distribution studies on ex vivo models to confirm the hepatobiliary disposition of the Gd-based magnetic resonance imaging contrast agent B22956/1. 2. Gd presence was selectively quantified allowing the determination of the time dependent disappearance of the drug from blood and its hepatic accumulation in mice after administration. Elemental mapping highlighted the drug distribution differences between healthy and diseased livers. XRF microanalyses showed that in CCl4-induced hepatitis, B22956/1 has greatly reduced hepatic accumulation, shown as a 20-fold reduction of Gd presence. Furthermore, a significant increase of Fe presence was found in steatotic compared with healthy livers, in line with the disease features. 3. The present results show that XRF might be useful in preclinical pharmacological studies with drugs containing exogenous elements. Furthermore, quantitative and high-sensitivity elemental mapping allows simultaneous detection of chemical variation, showing pathological conditions. This approach was useful in suggesting reduced B22956/1 accumulation in steatotic livers, thus opening possible new diagnostic perspectives for this drug.

The ongoing transition between micro and nano electromechanical systems (MEMS and NEMS) based on capacitive sensing requires a solution to the problem of pull-in instability and, on the whole, to the relevance of the electrostatic readout forces with respect to other forces to be sensed (inertial, magnetic,…). The paper analyzes the case of a differential accelerometer which is dimensioned to be subject to instability (i.e. with a negative equivalent stiffness), when combined with a constant voltage readout of ±1.8 V. A charge controlled readout principle, based on an electronic feedback loop, is presented. Its switching capacitor VLSI implementation, built in a CMOS 0.35 μm technology is used to demonstrate, through experimental results, that this approach is effective in the minimization of the electrostatic readout forces.

Large-area silicon drift detectors (SDDs) were used for the first time in the background condition of a collider for precision spectroscopy of the kaonic atom X-rays in the SIDDHARTA experiment for the study of the strong interaction in a low-energy regime. The measurements were performed at the DA Φ NE electron–positron collider (LNF, Italy), using gas targets of hydrogen, deuterium, helium-3, and helium-4. A test measurement using the kaonic 4 He X-rays showed an excellent performance of the SDD devices under the beam conditions, and a good background suppression capability using the time correlation between the kaonic atom X-rays and the back-to-back correlated K + K − pairs produced by φ decays.

The SIDDHARTA experiment (SIlicon Drift Detector for Hadronic Atom Research by Timing Application) had the aim to perform a precise measurement of K-series kaonic hydrogen x-rays and the first-ever measurement of the kaonic deuterium x-rays to determine the strong-interaction energy-level shifts and widths of the lowest lying atomic states. These measurements offer a unique possibility to precisely determine the isospin-dependent kaon-nucleon(KN) scattering lengths which are directly connected with the physics of the KN interaction. The experiment combined the excellent low-energy kaon beam generated at DAΦNE, allowing to use gaseous targets, with excellent fast X-rays detectors: Silicon Drift Detectors. SIDDHARTA was installed on DAΦNE in autumn 2008 and took data till late 2009. Apart of the kaonic hydrogen and kaonic deuterium measurements, we have performed the kaonic helium transitions to the 2 p level (L-lines) measurements: for the first time in a gaseous target for kaonic helium 4 and for the first time ever for kaonic helium 3. In this paper, an overview of this experiment and preliminary results are presented, together with future plans.

Semiconductor drift detectors (SDDs) are widely used in X-ray spectroscopy due to their excellent performances in terms of energy resolution and detection-rate. Suitable low noise readout electronics have to be designed in order to exploit the SDD intrinsic performances. The integration of this electronics in custom application specific integrated circuits (ASICs) is mandatory when the compactness of the detection system (detector and electronics) and the need to read out multi-elements SDDs are primary requirements. This work describes the development of three circuits for SDDs, which are a charge sensitive preamplifier operating in the pulsed reset regime, a fast shaping amplifier for high-count rates applications and a multi-channel ASIC that provides the whole analog processing and multiplexing of the signals from SDD arrays. The ASICs have been tested with SDDs with on-chip JFET and the results are presented here.

The K ¯ N system at rest makes a sensitive testing ground for chiral SU(3) symmetry in QCD, especially for the explicit symmetry breaking induced by the relatively large mass of the strange quark. At the DAΦNE electron-positron collider of Laboratori Nazionali di Frascati we study kaonic atoms, taking advantage of the low-energy kaons from Φ-mesons decaying nearly at rest. The low-energy antikaon-nucleon interaction in kaonic hydrogen and kaonic deuterium can be investigated under favorable conditions. The DEAR (DAΦNE Exotic Atom Research) experiment at LNF delivered the most precise data on kaonic hydrogen up to now. DEAR and its follow-up experiment SIDDHARTA (Silicon Drift Detector for Hadronic Atom Research by Timing Application) are using X-ray spectroscopy of kaonic atoms to measure the strong interaction induced shift and width of the ground state. SIDDHARTA is the first experiment on kaonic deuterium ever, and kaonic hydrogen is remeasured with improved precision. From the shift and width in K-p and K-d the isospin-dependent antikaon-nucleon scattering lengths can be determined, quantities essential as constraints for low-energy QCD.

The kaonic helium-4 3 d → 2 p X-ray transition was measured in a gaseous target, where Compton scattering in helium is negligible. The X-rays were detected with large-area Silicon Drift Detectors (SDDs) using the timing information of the K + K − pairs produced by ϕ decays at the DAΦNE e + e − collider. A new value of the strong interaction shift of the kaonic 4He 2p state was determined to be 0 ± 6 (stat) ± 2 (syst) eV , which confirms the recently obtained result by the KEK-PS E570 group.

The DAΦNE electron-positron collider at the Frascati National Laboratories has made available a unique “beam” of negative kaons. The SIDDHARTA (SIlicon Drift Detector for Hadronic Atom Research by Timing Application) experiment, successor of DEAR (DAΦNE Exotic Atom Research), aims at a precision measurement of the strong interaction shift and width of the fundamental 1s level, via the measurement of the x-ray transitions to this level, for kaonic hydrogen and kaonic deuterium. The final goal is to extract the isospin dependent antikaon-nucleon scattering lengths which contribute to the understanding of aspects of non-perturbative QCD in the strangeness sector. Other possible hadronic atoms measurements at DAΦNE are under study.

Hadronic atoms being Coulomb-bound systems in which the electron is substituted by a hadron like a negatively charged K meson are perfect probes for the study of strong interaction at lowest energies using x-ray spectroscopy. New large area x-ray detectors (silicon drift detectors, SDDs) were developed to provide excellent energy resolution as well as timing capability. For the first time large area SDDs were employed to measure the L-lines of kaonic helium at high precision thus succeeding in clarifying a puzzle persisting for 30 years since the 70's. An array of about 200 even more sophisticated SDDs (1 cm2 SDDs with monolithically integrated FET) will be used to perform precision measurements (i.e., at the eV level) of kaonic hydrogen and kaonic deuterium at the DAFNE Phi factory of LNF/Italy. The new x-ray detectors and their performance for precision experiments in the accelerator environment are presented.

With precise X-ray spectroscopy on kaonic hydrogen at the DAΦNE electron-positron collider at Laboratori Natzionali di Frascati the chiral symmetry breaking scenario in the strangeness sector will be investigated by studying the K − p and K − d s-wave interaction at threshold. The strong interaction induced shift and width of the kaonic hydrogen 1s atomic state was measured with DEAR (DAΦNE Exotic Atom Research) and in future with SIDDHARTA (Silicon Drift Detector for Hadronic Atom Research with Timing Application) the kaonic hydrogen system will be measured with utmost precision. In addition, data for the K − d system will become available for the first time. Kaonic hydrogen together with precision measurements of kaonic helium will allow the study of the sub-threshold Λ(1405) resonance, which might act as a doorway for the formation of antikaon-mediated deeply bound nuclear states in light nuclei. Therefore, these precision measurements are a powerful tool to test chiral symmetry breaking in systems with strangeness.

Au collisionneur d'electrons-positrons DAΦNE du Laboratoire National de Frascati (LNF), nous etudions les atomes kaoniques, prenant avantage du faisceau de kaons de faible energie produits par la desintegration de mesons Φ. L'interaction nucleon-kaon de basse energie dans l'hydrogene kaonique et le deuterium kaonique peut etre etudiee dans des conditions favorables. L'experience DEAR (Recherche sur les atomes exotiques a DAΦNE) a livre les resultants les plus precis qui existent sur l'hydrogene kaonique. DEAR et son successeur SIDDHARTA (Recherche sur les atomes kaoniques par detecteur Si et technique temporelle) utilisent la spectroscopie X des atomes d'hydrogene et de deuterium kaoniques pour etudier le deplacement du a l'interaction faible et la largeur du fondamental. A partir de ces quantites, il est possible de determiner la dependance en isospin des longueurs de collision kaon-nucleon, des quantites utiles pour mieux comprendre le bris de symetrie dans le secteur a etrangete nulle. Nous developpons actuellement les detecteurs X pour le projet SIDDHARTA. Nous allons utiliser une batterie de grands detecteurs Si a deplacement (SDDs) qui ont une excellente resolution en energie et en temps, ce qui va permettre une enorme diminution du bruit de fond et ainsi de surmonter la limite de precision des experiences anterieures.

The DAΦNE electron-positron collider at the Frascati National Laboratories has made available a unique “beam" of negative kaons providing unprecedented conditions for the study of the low-energy kaon-nucleon interaction, a field still largely unexplored. The DEAR (DAΦNE Exotic Atom Research) experiment at DAΦNE and its successor SIDDHARTA (SIlicon Drift Detector for Hadronic Atom Research by Timing Application) aim at a precision measurement of the strong-interaction shift and width of the fundamental 1s level, via the measurement of the X-ray transitions to this level, for kaonic hydrogen and kaonic deuterium. The aim is to extract the isospin-dependent antikaon-nucleon scattering lengths and to contribute to the understanding of aspects of chiral symmetry breaking in the strangeness sector.

Treatments delivered by proton therapy are affected by uncertainties on the range of the beam within the patient. To reduce these margins and improve feedback on treatment delivery, different projects are investigating real-time range control by imaging prompt gammas emitted along the proton tracks in the patient. This study supports the development of a prompt gamma camera using a knife-edge slit collimator to produce a reversed 1-dimensional projection of the beam path on a scintillation detector for treatments delivered in pencil beam scanning mode. The ability of this camera design to detect modifications of the beam penetration depth in a PMMA target was already demonstrated down to 1 mm accuracy for doses compatible with single pencil beams at low proton beam currents thanks to the HiCam photo-detection system. In order to fulfill the very demanding count rate capability required for prompt gamma imaging at clinical beam currents, a new, dedicated, cost-effective photo-detection system was designed. This 1-dimensional, high-energy gamma imaging device relies on two rows of 20 LYSO crystal slabs, directly coupled to SiPMs' arrays and readout by 40 independent acquisition channels in fast counting mode. A first prototype limited to 20 channels was implemented to benchmark the performances of various components and validate the adequate combination of crystal material, surface treatment, optical coupling and SiPMs. This prototype was tested during proton irradiation at the West German Proton Therapy Centre in Essen at clinical beam currents of several nA at nozzle exit.

The DAΦNE electron–positron collider at the Laboratori Nazionali di Frascati of INFN has made available a unique quality low-energy negative kaons “beam”, which is being used to unlock the secrets of the kaon–nucleon/nuclei interactions at low energies by the SIDDHARTA(-2) and the AMADEUS experiments. SIDDHARTA has already performed unprecedented precision measurements of kaonic atoms, and is being presently upgraded, as SIDDHARTA-2, to approach new frontiers. The AMADEUS experiment already started a data taking with a dedicated carbon target, plans to perform in the coming years precision measurements on kaon–nuclei interactions at low-energies, in particular to study the possible formation of kaonic nuclei and the Λ ( 1405 ) . The two experiments are briefly presented in this paper.

The study of the KbarN system at very low energies plays a key role for the understanding of the strong interaction between hadrons in the strangeness sector. At the DAFNE electron-positron collider of Laboratori Nazionali di Frascati we studied kaonic atoms with Z=1 and Z=2, taking advantage of the low-energy charged kaons from Phi-mesons decaying nearly at rest. The SIDDHARTA experiment used X-ray spectroscopy of the kaonic atoms to determine the transition yields and the strong interaction induced shift and width of the lowest experimentally accessible level (1s for H and D and 2p for He). Shift and width are connected to the real and imaginary part of the scattering length. To disentangle the isospin dependent scattering lengths of the antikaon-nucleon interaction, measurements of Kp and of Kd are needed. We report here on an exploratory deuterium measurement, from which a limit for the yield of the K-series transitions was derived: Y(K_tot), Accepted by Nuclear Physics A

The SIDDHARTA collaboration measured kaonic 3 He and 4 He 3d → 2p X-rays with gaseous targets at the DAΦNE e + e − collider. The 2p -state strong-interaction shifts and widths were precisely determined by using 144 high-resolution silicon drift detectors. The shift of K −4 He is in good agreement with theoretical calculations and consistent with the recent experimental result of KEK-PS E570. The shift of K −3 He is also determined for the first time. The newly determined widths are in agreement with optical model calculations.

Treatments delivered by proton therapy are affected by uncertainties on the range of the beam within the patient. To reduce these margins and deliver safer treatments, different projects are currently investigating real-time range control by imaging prompt gammas emitted along the proton tracks in the patient. This study reports on the development and test of a prompt gamma camera using a slit collimator to obtain a 1-dimensional projection of the beam path on a scintillator detector. A first prototype slit camera using the HICAM gamma detector, originally developed for low-energy gamma-ray imaging in nuclear medicine and modified for this purpose, was tested successfully up to 230 MeV beam energy. Results now confirm the potential of this concept for real-time range monitoring with millimeter accuracy in pencil beam scanning mode for the whole range of clinical energies. With the experience gained, a new prototype is under study for clinical beam currents. In this work, we present both the profiles obtained at 230 MeV using HICAM and the description of the new gamma camera prototype design.

In this work, we compare the performances of our CUBE circuit with respect to the typical performances of the external JFET transistor. We will show that CUBE enables to get superior energy resolution at short shaping time. This CUBE characteristic leads to practical advantages in several applications, like the possibility to have high-rate spectroscopy still preserving enough energy resolution to identify light elements. Alternatively, the CUBE advantages become evident in application wherever a very fast analysis is required, like in XRF mapping applications or in hand-held applications. Moreover, as known, the use of short peaking times reduces the impact of the detector leakage current on the total noise. Thus, CUBE allows to operate the detectors at room temperature (or slightly cooled). This introduces practical advantages in industrial applications avoiding the need of high power cooler stages and heat sinks, vacuum inside the SDD T08-like modules and slower startup and temperature stabilization phases. Measurements using a 25 mm2 SDD show a 260 eV FWHM resolution without any cooling of the detector; the room temperature was 25°C and the peaking time set to only 100 ns during measurement. By moderate cooling, the measured resolution was instead as good as 165 eV for a SDD temperature of 0 °C (at 300 ns peaking time). More examples of such performances will be shown as well.

Kaonic hydrogen atoms provide a unique laboratory to probe the kaon-nucleon strong interaction at the energy threshold, allowing an investigation of the interplay between spontaneous and explicit chiral symmetry breaking in low-energy QCD. The SIDDHARTA Collaboration has measured the $K$-series X rays of kaonic hydrogen atoms at the DA$\Phi$NE electron-positron collider of Laboratori Nazionali di Frascati, and has determined the most precise values of the strong-interaction induced shift and width of the $1s$ atomic energy level. This result provides vital constraints on the theoretical description of the low-energy $\bar{K}N$ interaction., Comment: 11 pages, 7 figures, Nuclear Physics A (in press) Special Issue on Strangeness Nuclear Physics

In this paper, we describe a front-end ASIC for the readout of multi-elements Silicon Drift Detectors (SDDs) specifically designed for high count-rate X-ray spectroscopy applications. In particular, the focus of this design is on the maximization of the event throughput and, at the same time, keeping a high energy resolution. The readout of a detector array by means of 8 separate channels allows increasing the maximum count-rate of the system. The use of one or more of these front-end ASICs allows the management of several readout channels required by a multi-SDD detector within a very compact detection system, as well as maintaining excellent noise performance. The use of a very-fast high-order processing filter and of an efficient pile-up rejection strategy allows minimizing the pile-up probability and maximizing the event throughput of the single channels for a given processing time. The use of a 3-phase peak-stretcher, together with a fast output multiplexer, permits to minimize the dead-time during the valid-data acquisition, practically to a value limited by the pure overlap of the shaped pulses. The ASIC is designed with the possibility of operating with the input JFET integrated on the detector itself as well as to operate in combination with an external preamplifier. The measured noise-contribution added by the front-end ASIC is only 2.9 electrons at 1.8 μs shaping time and just 4.1 electrons at the shortest 600 ns peaking time, exploiting at best the speed capability. In X-ray spectroscopy measurements, the ASIC connected to an SDD coupled to a CMOS preamplifier has allowed to achieve an energy resolution of 126 eV at 1.5 μs peaking time and 115 kcps/channel input rate, and 144 eV at 600 ns peaking time and 800 kcps/channel input rate.

In this work we present a new version of the circuit VERDI (Versatile Readout for Detector Integration), namely VERDI-3, an integrated circuit designed for the readout of different type of radiation detectors, from nitrogen-cooled Ge and Si(Li) detectors, to silicon drift detectors (SDDs), to scintillation detectors, to photomultipliers tubes and others. VERDI-3 has been designed to achieve better noise performances in all configurations than its predecessors. The circuit is characterized by a revised programmable shaping amplifier and baseline holder, a new embedded biasing network and a revised SPI communication with added functions. The new VERDI shares the same advantages in terms of compactness for multielement detector integration and low power solution as for the rest of its family. The results of the experimental characterization of the circuit when used with different detectors are presented in this work.

We present a monolithic CMOS charge preamplifier named “CUBE”. It is specifically designed to be used with Silicon Drift Detectors (SDD). We will show that the use a MOSFET as input transistor allows superior noise performances at very short shaping times respect to the state-of-the-art externally connected JFET devices. We will show the achievable energy resolutions using a 10mm2 reference SDD with different count-rates and with different analog and digital commercial filters. A state-of-the-art energy resolution (for a silicon detector) of 125 eV at 6 keV has been achieved with the optimum shaping time. Moreover, it will be shown that CUBE enables the use of an extremely fast-peaking time of only 100 ns with extraordinary good energy resolution of 149 eV. As a consequence we can state that, the CUBE preamplifier is very well suited for high count-rate spectroscopy applications. An example of the performance with output countrate up to 490 kcps will be reported.

The HICAM gamma camera is an imaging device recently developed in the framework of a European project, based on Silicon Drift Detectors (SDDs) as photodetectors. Although originally designed for low-energy gamma-ray imaging in nuclear medicine (140 keV of 99mTc), in this work we attempt to use the camera, suitably modified, to image high energy prompt gamma rays (2 to 7 MeV) emitted by a target irradiated by protons. The final objective of our experiment is to assess the feasibility of proton beam range measurements by prompt gamma imaging with a slit camera, and the HICAM camera was chosen for a first prototype. Although a SDD-based camera would not be fast enough for real treatment conditions, the prototype here employed benefited from the camera modularity, compactness, high resolution and low noise. The camera here employed is composed of 25 SDDs of 1 cm2 active area each, arranged in a 5×5 format, already used in clinical and research environments with a high intrinsic spatial resolution (∼1 mm). The SDD matrix has been coupled to a LYSO crystal (1cm thickness), to improve efficiency with high-energy gammas, and has been characterized preliminarily with a 60Co source. Good imaging performances have been obtained in this test. Moreover, results of a first test of the camera to detect prompt gammas emitted with a proton beam impinging on a plastic target are presented in this work.

A new Digital Pulse Processor (DPP), which is developed for radiation detectors especially suitable in applications where high rate and high-resolution spectroscopy are mandatory, is presented. An outstanding feature of the system is the fast peaking time (less than 0.1 usec) that allows processing an Input Count Rate (ICR) of 1Mcps with throughput of about 90% and a 2Mcps ICR with 70% live time, thanks to a high performances pile-up rejection and to the feature of automatic and adaptive filtering. Moreover, the system can synthesize and implement a class of optimum filters with arbitrary noise and constraints, both in time and in frequency domain. The DPP is suitable in spectrometers based on last generation Silicon Drift Detectors (SDD) used in very high count-rates and high-resolution regime. Characterization of the processor in different operative conditions is shown.

The DAΦNE electron–positron collider of the Laboratori Nazionali di Frascati of INFN has made available a unique quality low-energy negatively charged kaons “beam”, which is being used to study the kaon–nucleon/nuclei interactions by the SIDDHARTA-2 experiment and the AMADEUS Collaboration. The dynamics of the strong interaction processes in the nonperturbative regime is approached by lattice calculations and effective field theories (ChPT) which are still lacking experimental results in the lowenergy regime, fundamental for their good understanding. The studies of kaonic atoms and of the kaonic nuclear processes performed by SIDDHARTA-2 and AMADEUS play in this context a key-role.

The SIDDHARTA experiment (SIlicon Drift Detector for Hadronic Atom Research by Timing Application) had the aim to perform kaonic atoms X-ray transitions measurements, to better understand aspects of the low-energy QCD in the strangeness sector. The experiment combined the excellent low-energy kaon beam generated at DAΦNE, allowing to use gaseous targets, with excellent fast X-rays detectors: Silicon Drift Detectors. SIDDHARTA was installed on DAΦNE in autumn 2008 and took data till late 2009. Apart of the kaonic hydrogen and kaonic deuterium measurements, we have performed the kaonic helium transitions to the 2p level ( L -lines) measurements: for the first time in a gaseous target for helium4 and for the first time ever for kaonic helium3. The interest for such type of measurement was rather high, being it triggered by two reasons: the so-called "kaonic helium puzzle" (even if this was solved by KEK-PS E570 experiment, but a cross-check was useful) and some theoretical predictions of possible high energy shift (at the level of 10 eV). In this paper the preliminary results for the measurements to the 2p level ( L -series) for kaonic helium4 and kaonic helium3 are presented.

The SIDDHARTA experiment aims a precise measurement of K -series kaonic hydrogen x-rays and the first-ever measurement of the kaonic deuterium x-rays to determine the strong-interaction energy-level shifts and widths of the lowest lying atomic states. These measurements offer a unique possibility to precisely determine the isospin-dependent kaon-nucleon ( KN ) scattering lengths [1] which are directly connected with the physics of the KN interaction. Kaonic Helium transitions to the 2p level ( L -lines) were as well measured. The experiment has been performed at the DAΦNE e+e- collider which produces the Φ-resonance. The resulting low energy negative charged kaons, coming from the Φ decay, are well suited to be stopped efficiently in a high density gas target for producing such kind of atoms. As x-ray detectors, we employed 144 Silicon Drift Detectors developed especially for this experiment, having good energy resolution of 140 eV FWHM at 6keV and time resolution of sub-micro seconds. The data taking was completed in November 2009. In this paper, an overview of this experiment and preliminary results are presented, together with future plans.

The SIDDHARTA (SIlicon Drift Detector for Hadronic Atom Research with Timing Application) collaboration performed X-ray spectroscopy measurement of kaonic atoms at the DAΦNE e+e−collider. Low energy negative kaons from DAΦNE -factory were stopped in gaseous targets to produce kaonic atoms. We employed specially designed Silicon Drift Detectors(SDDs) to detect the kaonic X-rays. Based on the energy of kaonic- 4He 3d → 2p transition, we determined a new value of the 2p level strong-interaction shift of kaonic- 4He: 0 ± 6 (stat.)± 2 (syst.) eV[1]. Together with the result of recent E570 experiment[2] at the KEK-PS, a small shift (if any) of kaonic- 4He 2p level has become well established.

The instrument uses an SDD with nominal active area of 25 mm 2 and 135 eV Resolution at Mn Kα using a Cube preamplifier. The specified resolution is attained at all count rates achievable by the instrument. The X-ray tube has 4 W power, with 10-50 kV selectable in 1 kV steps, and typically incorporates a Rh anode, although other targets are available. A primary beam X-ray filter set is provided to improve sensitivity in specific regions of the spectrum. The coincidence of two laser beams, as illustrated in the schematic on Figure 2-right, defines the optimum stand-off position of the head. The combination of the laser beam positioning with CUBE preamplifier gives high analytical reproducibility in a portable instrument. The integrated camera records an image of the region around the analysis point, as shown in Figure 3, in which two points on a gold leaf surface (ca. 1500) were analysed. The spectra indicated a significantly higher Fe:Au ratio in Point 1 compared to Point 2. However, the recorded optical images show that the region around Point 1 has apparently undergone more erosion than the region around Point 2, perhaps explaining the spectral differences. The analyses of NIST standard bronzes containing 0.02 and 0.07% Pb and similar levels of Sn will be will be presented. Fundamental Parameters estimates of composition are reported. Light element performance using a He flush technique will be compared to electron beam microanalysis results.

In this work we present the circuit VERDI (VErsatile Readout for Detector Integration), an integrated circuit developed for the readout of different families of radiation detectors, from nitrogen-cooled Ge and Si(Li) detectors, to silicon drift detectors (SDDs), scintillation detectors, photomultipliers tubes and others. The circuit may represent a suitable solution when a compact integration between a multi-element detector and the front-end readout is needed to realize a compact and low-power detection module. The circuit includes 8 channels, each one composed by a charge preamplifier, a shaping amplifier, a gain stage, a baseline holder and a peak stretcher. An on-chip selector provides at the output of each channel the waveform of a specific stage, including an RC integrator for external digital processing of the signal. Alternatively, the 8 channels may be multiplexed on a single output. Different settings, like gain, shaping time, preamplifier compensation and others, may be externally programmed by SPI accordingly to the specific detector in use. Only the input JFET, feedback capacitor and reset device are left external to the ASIC, and must be chosen specifically for each detector. The results of preliminary experimental characterization of the circuit when used with different detectors are presented in this work.