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The purpose of the MU-RAY project is to develop an innovative approach to the study of volcanoes and their monitoring based on a particle physics approach.The test site is Vesuvio: one of the higher risk volcanoes in the world. In this context, muon radiography is an innovative method of enormous impact. This is an imaging technique which relies on the measurement, by means of a cosmic ray telescope, of the absorption in the volcano of muons with near-horizontal trajectories, produced by the interactions of cosmic rays with the atmosphere. Since 2003 this technique has been successfully used on volcanoes in Japan, providing pictures of their vertices with resolutions much better than those obtained with the traditional techniques based on gravimeters. Researchers from Naples and Florence are currently involved in the construction and testing of a prototype telescope based on the use of bars of plastic scintillator with a triangular section whose scintillation light is collected by special fibres (wavelength shifters) and transported to SiPM (Silicon photomultipliers). A complete prototype telescope, consisting of three xy scintillation planes and 1 m2 active area has been assembled and is now under test. © 2012 Elsevier B.V. All rights reserved.

International audience; For the J-PARC E40 experiment which aims to measure differential cross-sections of Σp scatterings, a system to detect scattered proton from Σp scatterings is under development. The detection system consists of scintillation fibers with a MPPC readout. A prototype and a readout electronics for MPPC have already been developed. The prototype consisting of a scintillation fiber tracker and a BGO calorimeter was tested with a proton beam of 80 MeV. Energy resolutions of the tracker of 22.0% (σ) and the calorimeter of 1.0% (σ) were obtained for 1 MeV and 70 MeV energy deposit, respectively. The prototype readout electronics has an ASIC for multichannel operation, EASIROC, and a Silicon TCP (SiTCP) interface to communicate with a DAQ system. Its data transfer rate measured was 14 kHz. Required performances for the prototype system have been achieved except for the energy resolution of the prototype fiber tracker.

EASIROC, standing for Extended Analogue Si-pm Integrated ReadOut Chip is a 32 channels fully analogue front end ASIC dedicated to readout SiPM detectors. This low power and highly versatile ASIC was developed from the chip SPIROC[1] which has been designed for the Analogue Hadronic Calorimeter foreseen at the International Linear Collider. EASIROC integrates a 4.5 V range 8-bit DAC per channel for individual SIPM gain adjustment. A multiplexed charge measurement from 160 fC up to 320 pC is available thanks to 2 analogue outputs. These charge paths are made of 2 variable gain preamplifiers followed by 2 tuneable shapers and a track and hold. A trigger path integrates a fast shaper followed by a discriminator the threshold of which is set by an integrated 10-bit DAC. These 32 trigger outputs can be used for timing measurements. The power consumption is lower than 5 mW/channel and unused features can be powered OFF to decrease the power. The chip has been designed in AMS 0.35 μm SiGe technology and 4000 dies have been produced in 2010. Its versatility allows its use in many photo detector experiments and is already used for PEBS, MuRAY, J-PARC and medical imaging.