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This viewpoint makes a theoretical effort to label the organization of the virtual sphere under new concepts: ‘encastellation’ and the ‘paradox of pluralism’. The former is a metaphorical synthesis of already-known concepts (selective exposure, polarization, homophily, echo chambers and filter bubbles). In the second case, we emphasize the existence of a ‘paradox of online pluralism’: the internet has increased the possibility for everyone to make their voice heard (in quantitative terms), but at the same time it appears to also be increasing the distance between voices, putting in jeopardy the achievement of the aims of the pluralist political system (in qualitative terms). In conclusion, we express doubts about the feasibility of the deliberative vision of democracy in the current virtual sphere.

We present a spectroscopic system constituted by a Silicon Drift Detector (SDD) coupled to a CMOS charge sensitive preamplifier, named SIRIO, specifically designed to reach ultimate low noise levels. The SDD, with an active area of $\hbox{13~mm}^2$ , has been manufactured by optimizing the production processes in order to reduce the anode current, successfully reaching current densities between $\hbox{17~pA/cm}^2$ and $\hbox{25~pA/cm}^2$ at $ + \hbox{20}~^\circ {\rm C}$ for drift fields ranging from 100 V/cm to 500 V/cm. The preamplifier shows minimum intrinsic noise levels of 1.27 and 1.0 electrons r.m.s. at $+\hbox{20}~^{\circ}{\rm C}$ and $-\hbox{30}~^{\circ}{\rm C}$ , respectively. At room temperature ( $ + 20^\circ {\rm C}$ ) the $^{55}{\rm Fe}$ 5.9 keV and the pulser lines have 136 eV and 64 eV FWHM, respectively, corresponding to an equivalent noise charge of 7.4 electrons r.m.s.; the noise threshold is at 165 eV. The energy resolution, as measured on the pulser line, ranges from 82 eV FWHM (9.4 electrons r.m.s.) at $ + \hbox{30}~^\circ {\rm C}$ down to 29 eV FWHM (3.3 electrons r.m.s.) at $ - \hbox{30}~^\circ {\rm C}$ .

Objectives A wide range of potential psychosocial, biological, genetic and environmental factors may interact with each other in determining suicidal behaviours. The aim of this study was to evaluate several biological parameters referred to the complete blood count values in 259 suicide attempters (SA) and 164 non-suicide attempters (control group), according to the lethality of suicidal behaviour. Methods After attempting suicide, subjects were admitted to the emergency ward of the IRCCS Ospedale Policlinico San Martino and later to the section of Psychiatry from 1 January 2014 to 31 June 2019. Socio-demographic and clinical characteristics, as well as blood cells, were collected. Results Individuals with high-lethality suicide attempts had a higher number of neutrophils, mean platelet volume, neutrophil-lymphocyte ratio, platelet-lymphocyte ratio, and lower number of lymphocytes relative to both those with low-lethality suicide attempts and control group. After regression analysis, only the mean platelet volume and platelet to lymphocyte ratio resulted associated with a high-lethality suicide attempt (HLSA). Conclusions Our findings provide potential and useful peripheral biological markers able to help clinicians in understanding the complex phenomenon of suicide. However, further studies are needed to confirm the present findings.

Arrays of silicon sensors can be used in those spectroscopic applications where a high event throughput is needed, for example, in synchrotron-based experiments. However, in such arrays, several noise contributions, beyond the well-known leakage, thermal, and flicker noises, can be present, which are absent in single-channel detectors. Additional noise is generated ultimately by the condition at the silicon/silicon-oxide interface, which in turn depends on the parameters of the silicon oxide over the not-implanted gaps. We discuss how to control this region to obtain the best spectroscopic performances.

Low-Gain Avalanche Detectors are gathering interest in the High-Energy Physics community thanks to their fast-timing and radiation-hardness properties, which are planned to be exploited, for example, in timing detectors for the upgrades of the ATLAS and CMS detectors at the High Luminosity LHC. This new technology has also raised interest for its possible application for photon detection in medical physics, imaging and photon science. The main characteristic of this type of device is a thin and highly-doped layer that provides internal and moderate gain, in the order of 10-20, that enhances the signal amplitude. Furthermore, the thin substrate of a few tens of microns allows fast carrier collection. This paper details on the fabrication technology, specifically developed at Brookhaven National Laboratory for the detection of minimum ionizing particles. The static electrical characterization and the gain measurements on prototypes will be reported, too., Comment: 13 pages, 9 figures

Author(s): Chambers, C; Walton, T; Fairbank, D; Craycraft, A; Yahne, DR; Todd, J; Iverson, A; Fairbank, W; Alamare, A; Albert, JB; Anton, G; Arnquist, IJ; Badhrees, I; Barbeau, PS; Beck, D; Belov, V; Bhatta, T; Bourque, F; Brodsky, JP; Brown, E; Brunner, T; Burenkov, A; Cao, GF; Cao, L; Cen, WR; Charlebois, SA; Chiu, M; Cleveland, B; Coon, M; Cree, W; Cote, M; Dalmasson, J; Daniels, T; Darroch, L; Daugherty, SJ; Daughhetee, J; Delaquis, S; Mesrobian-Kabakian, A Der; DeVoe, R; Dilling, J; Ding, YY; Dolinski, MJ; Dragone, A; Echevers, J; Fabris, L; Farine, J; Feyzbakhsh, S; Fontaine, R; Fudenberg, D; Giacomini, G; Gornea, R; Gratta, G; Hansen, EV; Heffner, M; Hoppe, EW; Hosl, J; House, A; Hufschmidt, P; Hughes, M; Ito, Y; Jamil, A; Jessiman, C; Jewell, MJ; Jiang, XS; Karelin, A; Kaufman, LJ; Kodroff, D; Koffas, T; Kravitz, S; Krucken, R; Kuchenkov, A; Kumar, KS; Lan, Y; Larson, A; Leonard, DS; Li, G; Li, S; Li, Z; Licciardi, C; Lin, YH; Lv, P; MacLellan, R; Michel, T; Mong, B; Moore, DC | Abstract: The search for neutrinoless double beta decay probes the fundamental properties of neutrinos, including whether or not the neutrino and antineutrino are distinct. Double beta detectors are large and expensive, so background reduction is essential for extracting the highest sensitivity. The identification, or 'tagging', of the $^{136}$Ba daughter atom from double beta decay of $^{136}$Xe provides a technique for eliminating backgrounds in the nEXO neutrinoless double beta decay experiment. The tagging scheme studied in this work utilizes a cryogenic probe to trap the barium atom in solid xenon, where the barium atom is tagged via fluorescence imaging in the solid xenon matrix. Here we demonstrate imaging and counting of individual atoms of barium in solid xenon by scanning a focused laser across a solid xenon matrix deposited on a sapphire window. When the laser sits on an individual atom, the fluorescence persists for $\sim$30~s before dropping abruptly to the background level, a clear confirmation of one-atom imaging. No barium fluorescence persists following evaporation of a barium deposit to a limit of $\leq$0.16\%. This is the first time that single atoms have been imaged in solid noble element. It establishes the basic principle of a barium tagging technique for nEXO.

In the future ATLAS Inner Tracker detector (ITk), several silicon strip modules will be biased by a single High-Voltage (HV) line, so that a switch between each strip sensor and the HV line is required to disconnect faulty sensors. Such a switch must satisfy strict requirements, such as being radiation hard, being able to sustain high voltages in the OFF state and being able to operate in a high magnetic field. At Brookhaven National Laboratory we conceived a new kind of solid-state switch that can potentially meet all the specs: it is a HV silicon vertical JFET. Before designing and fabricating the JFET, we did a study using numerical TCAD simulations that demonstrate the feasibility of fabricating the device in a standard planar technology. We report such simulations, highlighting in particular a few key parameters to which the JFET performances are most sensitive.

Abstract. Background: Climate factors may offer a stronger explanation of the variations in suicide rates compared with economic variables, even in the case of patients admitted involuntarily. Aims: We assessed the role of temperature as a determinant of the increased prevalence of suicide attempts (SA). Method: The sample comprised all cases of hospitalization for SA at the Psychiatric Clinic of the IRCCS Ospedale Policlinico San Martino between August 2013 and July 2018. For ambient temperature, data were provided by the Meteorological Observatory of the University of Genoa. Results: We noted a peak in suicides that was typically found in late spring and early summer due to global warming. Limitations: Other environmental/psychological factors contributing to the onset of an acute clinical event were not considered. The cross-sectional design of the study is another limitation. Conclusion: Further studies are needed to clarify the impact of climatic factors on suicide behavior and implement early intervention and preventive strategies for mental health.

A new class of silicon detectors, the Low-Gain Avalanche Diode (LGAD), has already shown excellent timing performances O(30-40 ps) and is being considered for several applications in the most diverse fields, ranging from timing in high energy physics experiments to medical imaging. LGADs typically exhibit a low to moderate gain (5 - 100), short rise time and high signal-to-noise ratio. Fine pixelization of LGADs is difficult to achieve, and to provide fine spatial resolution the AC-coupled LGAD (AC-LGAD) approach was introduced. In this type of device, the signal is capacitively induced on fine-pitched electrodes placed over an insulator. LGAD and AC-LGAD prototypes have been designed and fabricated at Brookhaven National Laboratory and segmented in both pixel matrices and strips. These prototypes are characterized via Transient Current Technique (TCT) using a fast-pulsed IR laser. The timing resolution is measured by studying the time coincidence between signals generated by a beta particle beam from a 90Sr source in two sensors or by using a collimated proton beam. Additional studies of the sensor's performance have been carried out, including the induced signal in neighbouring pixels and strips.

An Associated Particle Imaging (API) system consists of a high vacuum chamber where deuterium ions are accelerated on a tritium-loaded target, resulting in alpha particles and neutrons emitted back-to-back, the latter escaping the chamber and used, for example, for tomography of a high-Z sample. An accurate determination of the alpha position is crucial to determine the trajectory of the neutron. Existing API systems have several limitations which a semiconductor-based API detector placed inside the vacuum chamber should not present. The semiconductor material can be either silicon or diamond. In particular, large and fast signals are generated by the alpha interactions in these materials. A pixelated API detector will measure the time and hit position of the alphas produced in the reaction. However, during the lifetime of the generator, the semiconductor detector will be exposed to an intense flux of alpha particles that will degrade its performance over time. To assess the radiation hardness of silicon and diamond against the alpha particles, we exposed single diodes made of either of the two materials to a 5 MeV alpha flux generated by an 241Am radioactive source. During irradiation, the diodes were biased and mounted on current-sensitive preamplifier boards. We have therefore been able to measure insitu the evolution of the waveforms as the damage was accumulating in their substrates.

International audience; In view of the LHC upgrade phase towards the High Luminosity LHC (HL-LHC), the ATLAS experiment plans to upgrade the Inner Detector with an all-silicon system. The n-on-p silicon technology is a promising candidate to achieve a large area instrumented with pixel sensors, since it is radiation hard and cost effective. This paper reports on the last n-on-p pixel productions made by a collaboration between the FBK-CMM and the LPNHE in Paris, with some focus on the latest designs of thin sensors bump-bonded to the RD53A prototype chip, featuring a 100 × 25 and 50 × 50 µm^2 pixel cells. An overview of 2019–2020 test-beam results for the produced devices will be given, with a special perspective to the sensor design for the ATLAS ITk pixel construction. Preliminary results for new 50 µm thick n-on-p pixel sensors, still produced by LPNHE at FBK-CMM will be also presented.

We report on the results of a radiation campaign with neutrons and protons of Low Gain Avalanche Detectors (LGAD) produced by Hamamatsu (HPK) as prototypes for the High-Granularity Timing Detector (HGTD) in ATLAS. Sensors with an active thickness of 50μm were irradiated in steps of roughly 2 × up to a fluence of 3 ×1015neqcm−2 . As a function of the fluence, the collected charge and time resolution of the irradiated sensors will be reported for operation at −30 °C. We report on the results of a radiation campaign with neutrons and protons of Low Gain Avalanche Detectors (LGAD) produced by Hamamatsu (HPK) as prototypes for the High-Granularity Timing Detector (HGTD) in ATLAS. Sensors with an active thickness of 50~$\mu$m were irradiated in steps of roughly 2$\times$ up to a fluence of $3\times10^{15}~\mathrm{n_{eq}cm^{-2}}$. As a function of the fluence, the collected charge and time resolution of the irradiated sensors will be reported for operation at $-30^{\circ}$.

The main purpose of this article is to illustrate a case study regarding use of the municipality of Udine’s online platform Open Municipio, which was designed to broaden citizen participation in the management of the res publica. The study of the platform was carried out through three research methods. The first, a quantitative one, offered a picture of the citizens’ use of the platform. The second research, also of a quantitative nature, used a short questionnaire investigate motivations that led citizens to use the platform. The third qualitative research consisted in a series of informal interviews with some key people (politicians or administrative managers) who introduced the platform, or who manage and monitor it. The study shows that the introduction of the platform has not significantly affected participation, although Open Municipio is considered an important opportunity for making more transparent political decisions.

The High-Granularity Timing Detector is a detector proposed for the ATLAS Phase II upgrade. The detector, based on the Low-Gain Avalanche Detector (LGAD) technology will cover the pseudo-rapidity region of $2.4, Comment: 17 pages, 20 figures

This is a proceeding of 12th international "Hiroshima" Symposium on the Development and Application of Semiconductor Tracking Detectors. This paper studied the radiation hardness of low gain avalanche detector (LGAD) developed by the Novel Device Laboratory (NDL) in Beijing and The Institute of High Energy Physics (IHEP) of the Chinese Academy of Sciences. NDL LGAD sensors with different layouts, epitaxial resistivity, doping profile were irradiated up to 1.02E15 N_eq/cm^2 by 70MeV proton at Cyclotron and Radioisotope Center (CYRIC). The timing resolution of NDL LGAD reached 40-50$ps$ and the collected charge reached 3-4$fC$ after irradiation This is a proceeding of 12th international "Hiroshima" Symposium on the Development and Application of Semiconductor Tracking Detectors. This paper studied the radiation hardness of low gain avalanche detector (LGAD) developed by the Novel Device Laboratory (NDL) in Beijing and The Institute of High Energy Physics (IHEP) of the Chinese Academy of Sciences. NDL LGAD sensors with different layouts, epitaxial resistivity, doping profile were irradiated up to 1.02E15 N_eq/cm^2 by 70MeV proton at Cyclotron and Radioisotope Center (CYRIC). The timing resolution of NDL LGAD reached 40-50$ps$ and the collected charge reached 3-4$fC$ after irradiation

The essay analyzes if, how much and how there is an aptitude for professional updating and digital training by engineers and architects of Udine and Pordenone Provinces, as a consequence of the structural changes that these professions have had due to the diffusion of the most modern digital technologies. Particular em-phasis was given to the role of training as a tool to ensure a productive encounter between the subjective professionals’ conditions and the objective territorial con-text situation. About that, the following aspects have been analyzed: strengths and weaknesses of new technologies; factors that influence new technologies’ adop-tion and the skills centrality; policies to improve the territorial context; the future of the profession between the network and specialization; the role of training in the new technologies adoption linked to the lifelong learning.

nEXO is a proposed tonne-scale neutrinoless double beta decay ($0\nu\beta\beta$) experiment using liquid ${}^{136}Xe$ (LXe) in a Time Projection Chamber (TPC) to read out ionization and scintillation signals. Between the field cage and the LXe vessel, a layer of LXe ("skin" LXe) is present, where no ionization signal is collected. Only scintillation photons are detected, owing to the lack of optical barrier around the field cage. In this work, we show that the light originating in the skin LXe region can be used to improve background discrimination by 5% over previous published estimates. This improvement comes from two elements. First, a fraction of the $\gamma$-ray background is removed by identifying light from interactions with an energy deposition in the skin LXe. Second, background from ${}^{222}Rn$ dissolved in the skin LXe can be efficiently rejected by tagging the $\alpha$ decay in the ${}^{214}Bi-{}^{214}Po$ chain in the skin LXe., Comment: 11 pages, 12 figures

Measurements of electron drift properties in liquid and gaseous xenon are reported. The electrons are generated by the photoelectric effect in a semi-transparent gold photocathode driven in transmission mode with a pulsed ultraviolet laser. The charges drift and diffuse in a small chamber at various electric fields and a fixed drift distance of 2.0 cm. At an electric field of 0.5 kV/cm, the measured drift velocities and corresponding temperature coefficients respectively are 1 . 97 ± 0 . 04 m m ∕ μ s and ( − 0 . 69 ± 0 . 05 ) %/K for liquid xenon, and 1 . 42 ± 0 . 03 m m ∕ μ s and ( + 0 . 11 ± 0 . 01 ) %/K for gaseous xenon at 1.5 bar. In addition, we measure longitudinal diffusion coefficients of 25 . 7 ± 4 . 6 cm 2 /s and 149 ± 23 cm 2 /s, for liquid and gas, respectively. The quantum efficiency of the gold photocathode is studied at the photon energy of 4.73 eV in liquid and gaseous xenon, and vacuum. These charge transport properties and the behavior of photocathodes in a xenon environment are important in designing and calibrating future large scale noble liquid detectors.

We present the fabrication and the first functional tests on a new class of silicon devices: the AC-coupled Low-Gain Avalanche Diodes (AC-LGAD). Because of its good timing performance, the LGAD was originally developed to support the silicon tracker at High-Energy Physics experiments for the reconstruction of pile-up events originating from a same bunch crossing. Pile-up events happen in fact at slightly different times and adding a fourth dimension (the time) is crucial to resolve them. On the other hand, LGADs suffers from poor spatial resolution. AC-LGADs offer a solution to this drawback, while retaining the good timing performance. Test structures have been fabricated at BNL, using the internal silicon processing facility, and have been tested with fast electronics and radioactive sources. Large gains and fast signal have been measured, while the noise stays low and comparable to the standard LGAD case. Other wafer fabrications are ongoing to further improving performances and correct pitfalls in the very first fabrication.

This work was motivated by the possibility of simplifying the process steps on silicon device fabrication. This simplification could benefit other silicon detector fabrications and have the possibility of terminating the junction edges in other detector designs. This is our attempt of exploring the RIE trench technique onto silicon device process. This technique originated from the high-purified germanium (HPGe) detector fabrication. The results have shown good pixel isolations. It has also shown that the multiple guards to lower the potential from the active area are more effective for trenched guard rings than the planar-processed guard rings. Furthermore, it has shown that the inter-pixel capacitance decreases as the trench depth increases.

The detection of neutrons with precise timing, in the orders of a few tens of ps, has several scientific applications, for example in the measurement of the fast neutron flux in space. We illustrate the response of two different sensors, based on Low Gain Avalanche Detector (LGAD) technology, to fast neutrons generated by a Deuterium-Tritium (DT) source. The sensors were designed and fabricated at the Brookhaven National Laboratory with different geometries, doping profiles and substrate thicknesses. LGAD sensors are expected to provide good timing resolution, thanks to a combination of high signal-to-noise ratio and short rise time. Preliminary results from the two types of LGADs are compared.

A High-Voltage vertical JFET was conceived at Brookhaven National Laboratory (BNL) in the framework of the High-Voltage Multiplexing program for the ATLAS upgrade of the Inner Tracker (ITk), which was seeking for a rad-hard switch for the silicon strip modules. BNL’s HV-JFET are silicon devices based on a vertical structure. They have been entirely fabricated at BNL using the planar process routinely adopted for the fabrication of silicon sensors. Before irradiation, they show low leakage currents and high breakdown voltages in the OFF state and high currents in the ON state. These specs are good enough for the switch to be used for un-irradiated strip modules. Then, a neutron irradiation has been performed at the TRIGA nuclear reactor at Jozef Stefan Institute (Ljubljana, Slovenia) to assess the capability of this device to be usable after the ITk radiation levels. The irradiated devices have been characterized as well and the measurements are presented in this report.

When an uncollimated radioactive X-ray source illuminates a silicon PIN sensor, some ionizing events are generated in the nonimplanted gap between the active area of the sensor and the guard rings (GRs). Carriers can be collected by floating electrodes, i.e., electron accumulation layers at the silicon/oxide interface, and floating GRs. The crosstalk signals generated by these events create spurious peaks, replicas of the main peaks at either lower amplitude or of opposite polarity. We explain this phenomenon as crosstalk caused by charge collected on these floating electrodes, which can be analyzed by means of an extension of Ramo theorem.

In spite of the constant technological improvements in the field of detector development, X-ray fluorescence (XRF) in the soft X-ray regime remains a challenge. The low intrinsic fluorescence yield for energies below 2 keV indeed renders the applicability of low-energy XRF still difficult. Here, we report on a new multi-element multi-tile detection system currently under development, designed to be integrated into a soft X-ray microscopy end station. The system will be installed at the TwinMic beamline of Elettra synchrotron (Trieste, Italy) in order to increase the detected count rate by up to an order of magnitude. The new architecture is very versatile and can be adapted to any XRF experimental setup. Even though the first results of the previous version of such a multi-element system were encouraging, several issues still needed to be addressed. The system described here represents a further step in the detector evolution. It is based on four trapezoidal-shaped monolithic silicon drift detector tiles (matrices) with six hexagonal elements each equipped with a custom ultra-low noise application-specific integrated circuit readout. The whole signal processing chain has been improved leading to an overall increase in performances, namely, in terms of energy resolution and acquisition rates. The design and development of this new detection system will be described, and recent results obtained at the TwinMic beamline at Elettra will be presented. Future perspectives and improvements will also be discussed. Copyright © 2017 John Wiley & Sons, Ltd.

Detectors that can simultaneously provide fine time and spatial resolution have attracted wide-spread interest for applications in several fields such as high-energy and nuclear physics as well as in low-energy electron detection, photon science, photonics and imaging. Low-Gain Avalanche Diodes (LGADs), being fabricated on thin silicon substrates and featuring a charge gain of up to 100, exhibit excellent timing performance. Since pads much larger than the substrate thickness are necessary to achieve a spatially uniform multiplication, a fine pad pixelation is difficult. To overcome this limitation, the AC-coupled LGAD approach was introduced. In this type of device, metal electrodes are placed over an insulator at a fine pitch, and signals are capacitively induced on these electrodes. At Brookhaven National Laboratory, we have designed and fabricated prototypes of AC-coupled LGAD sensors. The performance of small test structures with different particle beams from radioactive sources are shown., 12 pages, 10 figures

In this paper we report on the characterization of the Hamamatsu VUV4 (S/N: S13370-6152) Vacuum Ultra-Violet (VUV) sensitive Multi-Pixel Photon Counters (MPPC)s as part of the development of a solution for the detection of liquid xenon scintillation light for the nEXO experiment. Various MPPC features, such as: dark noise, gain, correlated avalanches, direct crosstalk and Photon Detection Efficiency (PDE) were measured in a dedicated setup at TRIUMF. MPPCs were characterized in the range 163 K ≤ T ≤ 233 K . At an over voltage of 3 . 1 ± 0 . 2 V and at T = 163 K we report a number of Correlated Avalanches (CAs) per pulse in the 1 μ s interval following the trigger pulse of 0 . 161 ± 0 . 005 . At the same settings the Dark-Noise (DN) rate is 0 . 137 ± 0 . 002 Hz/mm 2 . Both the number of CAs and the DN rate are within nEXO specifications. The PDE of the Hamamatsu VUV4 was measured for two different devices at T = 233 K for a mean wavelength of 189 ± 7 nm . At 3 . 6 ± 0 . 2 V and 3 . 5 ± 0 . 2 V of over voltage we report a PDE of 13 . 4 ± 2 . 6 % and 11 ± 2 % , corresponding to a saturation PDE of 14 . 8 ± 2 . 8 % and 12 . 2 ± 2 . 3 % , respectively. Both values are well below the 24 % saturation PDE advertised by Hamamatsu. More generally, the second device tested at 3 . 5 ± 0 . 2 V of over voltage is below the nEXO PDE requirement. The first one instead yields a PDE that is marginally close to meeting the nEXO specifications. This suggests that with modest improvements the Hamamatsu VUV4 MPPCs could be considered as an alternative to the FBK-LF Silicon Photo-Multipliers for the final design of the nEXO detector.

Characterization of the vacuum ultraviolet (VUV) reflectance of silicon photomultipliers (SiPMs) is important for large-scale SiPM-based photodetector systems. We report the angular dependence of the specular reflectance in a vacuum of SiPMs manufactured by Fondazionc Bruno Kessler (FBK) and Hamamatsu Photonics K.K. (HPK) over wavelengths ranging from 120 nm to 280 nm. Refractive index and extinction coefficient of the thin silicon-dioxide film deposited on the surface of the FBK SiPMs are derived from reflectance data of a FBK silicon wafer with the same deposited oxide film as SiPMs. The diffuse reflectance of SiPMs is also measured at 193 nm. We use the VUV spectral dependence of the optical constants to predict the reflectance of the FBK silicon wafer and FBK SiPMs in liquid xenon.

Understanding reflective properties of materials and photodetection efficiency (PDE) of photodetectors is important for optimizing energy resolution and sensitivity of the next generation neutrinoless double beta decay, direct detection dark matter, and neutrino oscillation experiments that will use noble liquid gases, such as nEXO, DARWIN, DarkSide-20k, and DUNE. Little information is currently available about reflectivity and PDE in liquid noble gases, because such measurements are difficult to conduct in a cryogenic environment and at short enough wavelengths. Here we report a measurement of specular reflectivity and relative PDE of Hamamatsu VUV4 silicon photomultipliers (SiPMs) with 50 micrometer micro-cells conducted with xenon scintillation light (~175 nm) in liquid xenon. The specular reflectivity at 15 deg. incidence of three samples of VUV4 SiPMs is found to be 30.4+/-1.4%, 28.6+/-1.3%, and 28.0+/-1.3%, respectively. The PDE at normal incidence differs by +/-8% (standard deviation) among the three devices. The angular dependence of the reflectivity and PDE was also measured for one of the SiPMs. Both the reflectivity and PDE decrease as the angle of incidence increases. This is the first measurement of an angular dependence of PDE and reflectivity of a SiPM in liquid xenon., Comment: 21 pages, 15 figures, 6 tables. As accepted by JINST

International audience; In view of the LHC upgrade for the High Luminosity phase (HL-LHC), the ATLAS experiment plans to replace the Inner Detector with an all-silicon system. The n-on-p silicon technology is a promising candidate to achieve a large area instrumented with pixel sensors, since it is radiation hard and cost effective. The paper reports on the performance of thin 100 and 130μm n-in-p planar pixel sensors produced by FBK-CMM with active-edge technology in collaboration with LPNHE and INFN. Beam-test results are presented, with focus on the hit efficiency at the detector edge of a novel design consisting of a staggered deep trench.

The main purpose of this article is to illustrate a case study regarding use of the municipality of Udine’s online platform Open Municipio, which was designed to broaden citizen participation in the management of the res publica. The study of the platform was carried out through three research methods. The first, a quantitative one, offered a picture of the citizens’ use of the platform. The second research, also of a quantitative nature, used a short questionnaire investigate motivations that led citizens to use the platform. The third qualitative research consisted in a series of informal interviews with some key people (politicians or administrative managers) who introduced the platform, or who manage and monitor it. The study shows that the introduction of the platform has not significantly affected participation, although Open Municipio is considered an important opportunity for making more transparent political decisions.

The attitudes individuals have towards suicidal behaviour, be it their own or others', and their capacity for developing specific coping strategies are influenced by affective temperaments that play a significant role in emotional regulation. However, few studies have investigated these specific patterns with a view to stratify them according to the severity of suicidal behaviours in medical students. The Pearson χ2 test for the comparison of categorical variables, the t-test for independent samples of continuous variables and logistic regression analysis were used to compare the association among temperaments, coping strategies, and attitudes towards suicide in a sample of medical students who attend the School of Medicine, Genoa. Severe suicidal thoughts and behaviours relative to those who were not at risk for suicide were also revealed. The severe suicidal thought and behaviour group had significantly more anxious and cyclothymic temperaments together with a higher use of dis-adaptive, lower emotional focus coping strategies, and higher self-reproaching, criticizing, and judgemental attitudes towards suicidality compared to the no severe suicidal thought and behaviour group. The identified pattern suggests the need for clinicians to carefully consider the complex interplay of clinical features which characterize severely at risk for suicide young adults in order to develop effective and comprehensive prevention strategies.