Search results for "Vala"

The AX-PET demonstrator—Design, construction and characterization

2011

Abstract Axial PET is a novel geometrical concept for Positron Emission Tomography (PET), based on layers of long scintillating crystals axially aligned with the bore axis. The axial coordinate is obtained from arrays of wavelength shifting (WLS) plastic strips placed orthogonally to the crystals. This article describes the design, construction and performance evaluation of a demonstrator set-up which consists of two identical detector modules, used in coincidence. Each module comprises 48 LYSO crystals of 100 mm length and 156 WLS strips. Crystals and strips are readout by Geiger-mode Avalanche Photo Diodes (G-APDs). The signals from the two modules are processed by fully analog front-end …

Preliminary radiation hardness tests of single photon Si detectors

2010

Single photon Si detectors were fabricated by STMicroelectronics and fully characterized in standard operation conditions and after irradiations. Both single cells and arrays, of dimensions ranging from 5x5 up to 64x64, were electrically tested. The devices operation was studied as a function of the temperature from -25 degrees C to 65 degrees C varying the voltage over breakdown, from 5% up to 20% of the breakdown voltage before and after irradiation using both light ions, 10 MeV B ions to doses in the range 3x10(7)-5x10(10) cm(-2), and X-rays irradiations in the range 0.5-20 krad(Si). Optical characterization was performed using a laser at 659 nm and opportunely chosen filters to vary the…

Failure analysis of normally-off GaN HEMTs under avalanche conditions

2020

Gallium nitride (GaN) high electron-mobility transistors (HEMTs) are promising devices in the power electronics field owing to their wide bandgap (WBG). However, all the potential advantages provided by their WBG require reliability improvement. In industrial applications, robustness is one of the main factors considered by circuit designers. This study focuses on the observation of the degradation behavior of the main waveforms of unclamped inductive-switching (UIS) test circuits of two different commercial GaN HEMT structures. The relevance of this study lies in the potential applications of these devices to high-voltage applications and automotive systems where they are subjected to many…

Energy and time resolution for a LYSO matrix prototype of the Mu2e experiment

2016

We have measured the performances of a LYSO crystal matrix prototype tested with electron and photon beams in the energy range 60$-$450 MeV. This study has been carried out to determine the achievable energy and time resolutions for the calorimeter of the Mu2e experiment.

Valantia deltoidea (Rubiaceae) sulle Madonie (Sicilia)

2011

Valantia deltoidea, a therophyte endemic to Sicily, so far known only from its locus classicus on the Rocca Busambra (Palermo, Province) has recently been found at the foot of the Serre di Quacella (Madonie, on dolomite rock, about 1300 m altitude. Besides outlines of taxonomical characteristics of such species, the data on the new locality and the updated distribution are provided here.

NEOTECTONIC ACTIVITY AND EMISSION OF FLUIDS IN THE NORTHWEST SICILY CHANNEL

The southern Sicilian coast represents an important contribution to Italian tourism, the Sicily Channel is an important communication path because at the top of its seafloor there are many pipelines, and submarine communication cables which are laid to carry signals, and which are very important to the minor islands. In this work, we are presenting results of the detailed geomorphological and seismostratigraphic analysis based on new very high-resolution dataset (multibeam and CHIRP) acquired during the ACUSCAL 2015 Cruise. We also used low resolution bathymetric and seismic data provided from online database (ViDEPI, GEBCO, EMODnet). This study allows us to reconstruct the tectonic volcani…

Recensione a: Valafrido Strabone, La visione di Vetti. Il primo viaggio poetico nell’Aldilà, a cura di Fr. Stella e Fr. Mosetti Casaretto, Pisa 2009 …

2011

Viene recensita l'ediz., con trad. ital., di Valafrido Strabone, La visione di Vetti. Il primo viaggio poetico nell’Aldilà, a cura di Fr. Stella e Fr. Mosetti Casaretto, Pisa 2009. Si tratta di un testo mediolatino di epoca carolingia, in esametri, nel quale viene narrata la prima "visione" poetica dell'aldilà (narrazione del viaggio dello stesso protagonista Vettino all'Inferno e al Paradiso).

Measurements of Silicon Photomultipliers Responsivity in Continuous Wave Regime

2013

We report on the electrical and optical characterization, in continuous wave regime, of a novel class of silicon photomultipliers fabricated in standard planar technology on a silicon p-type substrate. Responsivity measurements, performed with an incident optical power down to tenths of picowatts, at different reverse bias voltages and on a broad (340–820 nm) spectrum, will be shown and discussed. The device temperature was monitored, allowing us to give a physical interpretation of the measurements. The obtained results demonstrate that such novel silicon photomultipliers are suitable as sensitive power meters for low photon fluxes.

Suomen yleiskartta

1863

CCDC 1950549: Experimental Crystal Structure Determination

2019

Related Article: Guillermo Fiorini, Luca Carrella, Eva Rentschler, Pablo Alborés|2020|Dalton Trans.|49|932|doi:10.1039/C9DT03561C