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The X-ray spectroscopy measurements of light kaonic atoms’ deexcitation towards the fundamental level provide unique information on the low-energy Quantum ChromoDynamics (QCD) in the strangeness sector, being a direct probe of the kaon/nucleon interaction at threshold, unobtainable through the scattering experiments. In this framework, the SIDDHARTA-2 collaboration is going to perform the first kaonic deuterium 2p → 1s transition measurement at the DAΦNE collider of Istituto Nazionale di Fisica Nucleare – Laboratori Nazionali di Frascati. Combining this measurement with the kaonic hydrogen one performed by SIDDHARTA in 2009 it will be possible to obtain, in a model-independent way, the isospin-dependent antikaon-nucleon scattering lengths. The paper introduces the SIDDHARTA-2 setup, an upgraded version with respect to the one used for the kaonic hydrogen measurement, dedicated to the ambitious kaonic deuterium measurement, together with the preliminary results obtained during the kaonic helium run, preparatory for the SIDDHARTA-2 data taking campaign.

The aim of the SIDDHARTA-2 experiment is to perform the first measurement ever of the width and shift induced by the strong interaction to the 2 p → 1 s energy transition of kaonic deuterium. This ambitious goal implies a challenging task due to the very low X-ray yield of kaonic deuterium, which is why an accurate and thorough characterization of the experimental apparatus is mandatory before starting the data-taking campaign. Helium-4 is an excellent candidate for this characterization since it exhibits a high yield in particular for the 3 d → 2 p transition, roughly 100 times greater than that of the kaonic deuterium. The ultimate goal of the work reported in this paper is to study the performances of the full experimental setup in view of the kaonic deuterium measurement. This is carried out by measuring the values of the shift and the width for the 3 d → 2 p energy transition of kaonic helium-4, induced by the strong interaction. The values obtained for these quantities, for a total integrated luminosity of ∼31/ p b , are ε 2 p = 2.0 ± 1.2 (stat) ± 1.5 (syst) eV and Γ 2 p = 1.9 ± 5.7 (stat) ± 0.7 (syst) eV . The results, compared to the value of the shift measured by the SIDDHARTA experiment ε 2 p = 0 ± 6 (stat) ± 2 (syst) eV , show a net enhancement of the resolution of the apparatus, providing strong evidence of the potential to perform the challenging measurement of the kaonic deuterium. [ABSTRACT FROM AUTHOR]

Kaonic atom X-ray spectroscopy is a consolidated technique for investigations on the physics of strong kaon–nucleus/nucleon interaction. Several experiments have been conducted regarding the measurement of soft X-ray emission (<20 keV) from light kaonic atoms (hydrogen, deuterium, and helium). Currently, there have been new research activities within the framework of the SIDDHARTA-2 experiment and EXCALIBUR proposal focusing on performing precise and accurate measurements of hard X-rays (>20 keV) from intermediate kaonic atoms (carbon, aluminum, and sulfur). In this context, we investigated cadmium–zinc–telluride (CdZnTe or CZT) detectors, which have recently demonstrated high-resolution capabilities for hard X-ray and gamma-ray detection. A demonstrator prototype based on a new cadmium–zinc–telluride quasi-hemispherical detector and custom digital pulse processing electronics was developed. The detector covered a detection area of 1 cm2 with a single readout channel and interesting room-temperature performance with energy resolution of 4.4% (2.6 keV), 3% (3.7 keV), and 1.4% (9.3 keV) FWHM at 59.5, 122.1, and 662 keV, respectively. The results from X-ray measurements at the DAΦNE collider at the INFN National Laboratories of Frascati (Italy) are also presented with particular attention to the effects and rejection of electromagnetic and hadronic background. [ABSTRACT FROM AUTHOR]

Water leakage is one of main problems of distribution infrastructures, reaching unacceptable peaks of 50% of water lost in old networks in several countries. In order to address this challenge, we present an impedance sensor able to detect small water leaks (below 1 L of released volume). The combination of real-time sensing and such a sensitivity allows for early warning and fast response. It relies on a set of robust longitudinal electrodes applied on the external surface of the pipe. The presence of water in the surrounding medium alters its impedance in a detectable way. We report detailed numerical simulations for the optimization of electrode geometry and sensing frequency (2 MHz), as well as the successful experimental proof in the laboratory of this approach for a pipe length of 45 cm. Moreover, we experimentally tested the dependence of the detected signal on the leak volume, temperature, and morphology of the soil. Finally, differential sensing is proposed and validated as a solution to reject drifts and spurious impedance variations due to environmental effects. [ABSTRACT FROM AUTHOR]

A key milestone for the pervasive diffusion of wireless sensing nodes for smart monitoring of water quality and quantity in distribution networks is the simplification of the installation of sensors. To address this aspect, we demonstrate how two basic contactless sensors, such as piezoelectric transducers and strip electrodes (in a longitudinal interdigitated configuration to sense impedance inside and outside of the pipe with potential for impedimetric leak detection), can be easily clamped on plastic pipes to enable the measurement of multiple parameters without contact with the fluid and, thus, preserving the integrity of the pipe. Here we report the measurement of water flow rate (up to 24 m3/s) and temperature with ultrasounds and of the pipe filling fraction (capacitance at 1 MHz with ~cm3 resolution) and ionic conductivity (resistance at 20 MHz from 700 to 1400 μS/cm) by means of impedance. The equivalent impedance model of the sensor is discussed in detail. Numerical finite-element simulations, carried out to optimize the sensing parameters such as the sensing frequency, confirm the lumped models and are matched by experimental results. In fact, a 6 m long, 30 L demonstration hydraulic loop was built to validate the sensors in realistic conditions (water speed of 1 m/s) monitoring a pipe segment of 0.45 m length and 90 mm diameter (one of the largest ever reported in the literature). Tradeoffs in sensors accuracy, deployment, and fabrication, for instance, adopting single-sided flexible PCBs as electrodes protected by Kapton on the external side and experimentally validated, are discussed as well. [ABSTRACT FROM AUTHOR]

Gain amplitude modulation multichannel ASIC (GAMMA) is a 16-channel application specified integrated circuit (ASIC), designed in 0.35- $\mu \text{m}$ technology to read the charge provided by silicon photomultipliers (SiPMs) on a wide amplitude range. This chip was designed to satisfy the demanding requirements of the INFN the GAMMA project, where a 3” $\times3$ ” large lanthanum bromide crystal is to be read by SiPMs, aiming at state-of-the-art energy resolution. Because the energy range of the application is 100 keV–20 MeV, signals in a wide dynamic range (DR) have to be processed by the ASIC. This wide DR requirement raised the necessity of an adaptive gain change solution in order to guarantee a high signal-to-noise ratio together with a large full-scale range. While the ASIC input stage features a programmable static gain, the analog filtering channel exploits a self-triggered gated integrator stage with an automatically adjusted gain for each detected input current pulse; one of the following values is selected: 10, 2, or 0.83 [mV/pC]. The gated integrator gain is predictively adjusted before the circuit reaches saturation due to a time-gated threshold mechanism and provides negligible charge loss when the gain is switched (< 20 fC). A preintegration feature is also implemented in order to get rid of nonlinearity due to delays in the integration phase that could take place in a multi-ASIC system. The ASIC uses 5- and 3.3-V bias voltages, the overall power consumption being 280 mW. The ASIC was tested with a $12\times12$ SiPMs matrix coupled with a 3 inch LaBr 3, providing good spectroscopic performances (2.6% at the 137Cs photopeak emission energy of 662 keV), and was also tested irradiating the SiPMs with fast, bright NUV light pulses, in order to explore the ASIC wide range coverage while simulating the scintillation light emission of a lanthanum bromide crystal. [ABSTRACT FROM AUTHOR]

LAILA is a miniaturized eight-channel electronic readout system for compact γ-ray detectors, combining high-resolution spectroscopy capability with position sensitivity. Compactness is achieved by the combination of a novel CMOS front-end ASIC (Application-Specific Integrated Circuit) for analog processing of a large signal current from Silicon PhotoMultiplier (SiPM) solid-state photodetectors, with a microcontroller-based data acquisition system. The adoption of automatic gain regulation in the gated-integrator stage of the ASIC offers an 84 dB dynamic range, combining single-photon sensitivity with an extended input photon energy range (20 keV–4 MeV, using 30 μm-cell SiPMs). Using this module with properly merged 144 SiPM pixels coupled to a 3 in.-thick lanthanum bromide scintillation crystal, a 3% energy resolution at 662 keV and 1 cm spatial resolution in the estimation of the interaction coordinates are experimentally demonstrated in this work. [ABSTRACT FROM AUTHOR]

This work presents throughput-enhanced readout ASIC (TERA), an integrated multichannel analog pulse processor (APP), suitable for processing signals generated from solid-state detectors, such as silicon drift detectors (SDDs) coupled to pulsed reset-type charge-sensitive amplifiers (CSAs). In particular, this development targets applications at high count rates (≈Mcps) in energy-dispersive X-ray spectroscopy. The demonstrator chip is composed of four parallel readout channels. Each channel includes a seventh-order semi-Gaussian shaping amplifier with controllable shaping times and full-scale ranges, followed by a peak stretcher and switched-capacitor analog memory. Each channel is also equipped with a dedicated peak detector and a novel pile-up rejection (PUR) logic. Each pair of channels can be optionally digitized by a 12-bit on-chip successive-approximation-register (SAR) analog-to-digital converter (ADC), providing a digital output at a maximum sampling rate of 2.5 Msps. The architecture achieves high throughput and satisfactory energy resolution. In fact, in 55Fe spectroscopy measurements, when using the shortest shaping pulsewidth of 200 ns, a full-width at half-maximum (FWHM) Mn Kα line of 159.4 eV (12.5 e−rms) was obtained at low rates (10 kcps). This energy resolution can be achieved, thanks to the minimization of the effect of the ballistic deficit, achieved by optimizing the SDD detector in terms of optimum biasing, low operating temperature (−37 °C), and small size (1-mm diameter). At 1.61 Mcps/channel input rate, an output count rate of 1.09 Mcps/channel and a resolution of 205.1 eV (19.7 e−rms) were achieved with a 4-mm-diameter SDD and optimum PUR settings. Simultaneous multichannel acquisition has been successfully performed. Such high-rate performances are, to our knowledge, the best ones reported so far for an APP, based on a spectroscopy-grade application-specific integrated circuit (ASIC), and very close to those achievable by a standard digital pulse processor (DPP). Therefore, TERA can represent an attractive, compact, and scalable pulse processing solution for high-rate multichannel energy-dispersive X-ray detection systems. [ABSTRACT FROM AUTHOR]

The importance of earth observation (EO) from space is felt today more than ever in many different fields of human activity. Governments, international organizations, military bodies, private industry, and even individuals benefit every day of the products of spaceborne remote sensing technology. In this paper, we present a brief overview of some of the main trends in the EO scenario, focusing on the emergence of a new paradigm for EO space systems namely: the ongoing, disruptive shift from large satellites to constellations of small spacecraft, fueled by the recent introduction of several key technologies, such as for instance electric propulsion. We present the outline of a tool specifically conceived to assist the system architect in the early design phase of an EO constellation of microsatellites equipped with electric thrusters. A case study is presented for the application of a multisegmented constellation, with visual, thermal infrared, and radar components to remotely monitor a national railway network. We conclude that, in spite of the complexity of modern small satellite constellations, preliminary design can be successfully performed in a simplified and effective way. [ABSTRACT FROM AUTHOR]

ARDESIA, a four‐channel X‐ray spectrometer based on silicon drift detectors (SDDs), is presented. It has been developed for synchrotron applications targeting especially X‐ray fluorescence (XRF) and X‐ray absorption spectroscopy (XAS) with good energy resolution at high count rates (a few Mcps per second). The main target applications are XRF and XAFS techniques. The system features a 2 × 2 monolithic array of 5‐mm‐pitch SDDs cooled with a double Peltier scheme and coupled to a four‐channel CUBE charge preamplifier. Different digital pulse processors allowing operation in Mcps per second count rates are employed. The results of preliminary characterization measurements performed at both the LNF DAΦNE‐Light DXR1 beamline and the ESRF LISA BM‐08 are reported, in particular, XRF measurements on low atomic number elements (down to the Carbon K‐line, 270 eV) and extended X‐ray absorption fine structure of trace materials in pyrite. [ABSTRACT FROM AUTHOR]

Sterile neutrinos appear in minimal extensions of the Standard Model of particle physics. If their mass is in the keV regime, they are viable dark matter candidates. One way to search for sterile neutrinos in a laboratory-based experiment is via the analysis of β-decay spectra, where the new neutrino mass eigenstate would manifest itself as a kink-like distortion of the β-decay spectrum. The objective of the TRISTAN project is to extend the KATRIN setup with a new multi-pixel silicon drift detector system to search for a keV-scale sterile neutrino signal. In this paper we describe the requirements of such a new detector, and present first characterization measurement results obtained with a 7 pixel prototype system. [ABSTRACT FROM AUTHOR]

Traditionally, the overlap between electronics and aerospace technology was limited to avionics, radars, satellites, and telecommunications. Sensors networks are emerging as an additional area of relevant interaction. In fact, in addition to the classical paradigm in which on-board sensors improve the navigation and control of aerial vehicles, e.g., in the fly-by-wire context, novel paradigms of cooperation between fixed networks of ground sensors and airborne ones are emerging today, especially for monitoring the environment. In this paper, we review current development trends and open challenges with reference to practical examples. We focus on the role of sensor miniaturization, energy harvesting, energy-aware communication architectures, and data fusion. Multidisciplinary development teams, with expertise spanning from microelectronics and data analysis, to operation of UAV swarms are expected to be necessary to address these challenges. [ABSTRACT FROM AUTHOR]

There is increasing clinical use of combined positron emission tomography and MRI, but to date there has been no clinical system developed capable of simultaneous single-photon emission computed tomography (SPECT) and MRI. There has been development of preclinical systems, but there are several challenges faced by researchers who are developing a clinical prototype including the need for the system to be compact and stationary with MRI-compatible components. The limited work in this area is described with specific reference to the Integrated SPECT/MRI for Enhanced stratification in Radio-chemo Therapy (INSERT) project, which is at an advanced stage of developing a clinical prototype. Issues of SPECT/MRI compatibility are outlined and the clinical appeal of such a system is discussed, especially in the management of brain tumour treatment. [ABSTRACT FROM AUTHOR]

A dual-channel credit-card-sized impedance cell counter featuring a throughput of 2000 cell/s and detection of single yeast cells (5 μm) with a signal-to-noise ratio of 20 dB is presented. Its compactness is achieved by a CMOS ASIC combining a lock-in impedance demodulator with an oversampling 20-bit ΣΔ ADC and real-time peak detection embedded in field-programmable gate array. The module is coupled to a dielectrophoretic cell-sorting microfluidic device, offering compact and label-free electrical readout that replaces the need for a fluorescence microscope and, thus, is suitable for point-of-care diagnostics. The independent role of each dimension of the planar sensing microelectrodes is demonstrated, with simulations and experiments, along with its relevant effect on the spectrum of thin channels, deriving useful design guidelines. [ABSTRACT FROM PUBLISHER]