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Abstract The possibility to use a mini-phoswich detector to identify ions in the region of Z ∼ 10 is explored in the framework of the NUMEN project. The NUMEN program, aimed at the investigation of the nuclear matrix elements connected to the neutrinoless double beta decay by means of double charge exchange nuclear reactions, foresees very high fluencies, which prevent the use of standard silicon as stop detectors. The need of reasonable radiation hardness, together with a total energy resolution around 2% and a high granularity, makes scintillators possible candidates. Promising results are obtained using an array of plastic + inorganic phoswich scintillators readout by means of Silicon Photo Multipliers. [ABSTRACT FROM AUTHOR]

Abstract: We present the preliminary results of the characterization of silicon detectors in terms of Photon Detection Efficiency (PDE). The precision measurements are performed at controlled temperature, using a specially suited setup based on a monochromator, an integrating sphere to randomize the incident light and a calibrated reference photodiode. We exploit a measurement technique that we recently devised, based on single photon counting with subtraction of dark noise, and avoiding as much as possible cross-talk and afterpulses. We describe in detail the experimental setups and the techniques utilized to measure the PDE. The achieved results are here discussed in order to establish a methodology capable to give very precise PDE values for solid-state photomultiplier detectors. [Copyright &y& Elsevier]

We outline the possible applications of newly developed single photon avalanche detectors (SPAD) operating at low voltage and fabricated in silicon planar technology, reporting on tests done with scintillators. We envisage the integration of large arrays of identical sensors, employing a common read-out mode in order to achieve a high resolution and high sensitivity solid state photomultiplier. The applications of such a device would be many, particularly if we consider that we are also working on the production of microoptical components, perfectly suited for the lossless coupling of these photosensors to several light sources (lasers, ordinary and scintillating fibers, scintillators, optical devices), by exploiting the promising deep lithography with ions (DLI) technology. Crossed time-of-flight and charge measurements between SPADs and usual photomultipliers, coupled to scintillators, have allowed to compare their relative performance. Specific issues regarding the SPAD and the scintillating fiber readout are presented, also in view of possible applications in the field of particle/radiation tracking systems [ABSTRACT FROM PUBLISHER]

Abstract: A prototype demonstrator for the online monitoring of short–medium term radioactive waste repositories is currently under development at INFN-LNS. Such a system is planned to be distributed, fine-grained, robust, reliable, and based on low-cost components. With the main purpose of counting gamma radiation, we implemented a new kind of mini-detector based on silicon photomultipliers and scintillating fibers that behaves like a cheap scintillating Geiger–Muller counter and is suitable to be deployed in the shape of a grid around waste drums. [Copyright &y& Elsevier]

Abstract: We developed and tested a simple prototype of thermal neutron detector suitable for inexpensive deployment in the decommissioning and storage of radioactive waste, as well as for mapping the flux in the out-of-core regions of fission reactors. Though the prototype version we tested provides the neutron rate by subtracting the gamma background measured with a twin detector insensitive to neutrons, a simple geometrical improvement can strongly reduce the gamma contribution. [Copyright &y& Elsevier]

Abstract: The readout of a cheap scintillating fibre was implemented by means of a new solid-state device (Silicon Photomultiplier, SiPM), able to detect very tiny light pulses. The GEANT3.21 code was adopted to simulate the counting detection efficiency and the energy deposited inside the scintillating fibre due to the radiation of a radioactive gamma source. The results obtained show the capability to detect gamma rays producing as few as 3–4 photoelectrons. The new devices may have many applications in radioactivity metrology. [Copyright &y& Elsevier]

Abstract: The development of an endorectal PET Time Of Flight (TOF) probe prototype compatible with MRI, is going to be carried out within the INFN project TOPEM. Time resolution and depth of interaction (DOI) will allow to significantly improve the image quality, by rejecting those events coming from the surrounding tissues and correcting the parallax error. The activity described in this paper is focused on the characterization of the single pixel detector of the probe, consisting of a LYSO finger scintillator read out at both ends by means of a pair of Silicon Photomultipliers (SiPM). Energy, timing and DOI resolutions have been measured with a proper surface treatment and wrapping, finding very competitive results for DOI and timing. [Copyright &y& Elsevier]