Response of Silicon photo-multipliers to a constant light flux

The response of a Silicon Photomultiplier to a constant illumination has been interpreted in term of Geiger- Mueller avalanche frequency, actually correlated to the photon flux via the photon detection efficiency. The hypothesis has been verified in laboratory tests and applied throughout the development of a device for real-time dosimetry in mammography

Silicon photomultiplier readout of a scintillating noble gas detector for homeland security

Detectors based on scintillation by high pressure 4He are a viable technology for instruments against the illicit trafficking of nuclear material. A design based on the use of solid state photodetectors is presented in this paper and the preliminary qualification discussed

Recent results on GaAs detectors - 137

The present understanding of the charge collection in GaAs detectors with respect to the materials used and its processing are discussed. The radiation induced degradation of the charge collection efficiency and the leakage current of the detectors are summarised. The status of strip and pixel detectors for the ATLAS experiment are reported along with the latest results from GaAs X-ray detectors for non-high energy physics applications.Comment: 7 pages. 4 postscript figures + 1 postscript preprint logo + 1 LaTeX file + 1 style file. Also available at http://ppewww.ph.gla.ac.uk/preprints/97/05

Photon-number statistics with Silicon photomultipliers

We present a description of the operation of a multi-pixel detector in the presence of non-negligible dark-count and cross-talk effects. We apply the model to devise self-consistent calibration strategies to be performed on the very light under investigation

SiPM technology applied to radiation sensor development

The Silicon Photo-Multiplier (SiPM) being yet in its infancy, a full protocol for the sensor characterization has been developed and implemented at the Physics Department of Universita\u2019 dell\u2019Insubria. Sensors from different producers have been analyzed and compared, in view of the integration in the instruments for radiation detection. Exemplary illustrations are reported here, together with the first results on real-time dosimetry in mammography

Mammodos – In-Vivo Dosimetry in Mammography

In the scope of the RAPSODI EU research project, a prototype detector for in-vivo dose measurements in Mammography was developed. We present and discuss first results on the system qualification, in particular on the linear dynamic range, the energy response and the radiological as well as optical transparency of the detector

Commissioning and Field Tests of a Van-Mounted System for the Detection of Radioactive Sources and Special Nuclear Material

MODES-SNM project aimed at developing a mobile/portable modular detection system for radioactive sources and Special Nuclear Material (SNM). Its main goal was to deliver a tested prototype capable of passively detecting weak or shielded radioactive sources with accuracy higher than that of currently available systems. By the end of the project all the objectives have been successfully achieved. Results from the laboratory commissioning and the field tests are presented in this publication

Radiation tests of semiconductor detectors

This thesis investigates the response of Gallium Arsenide (GaAs) detectors to ionizing irradiation. Detectors based on π-υ junction formed by deep level centers doping. The detectors have been irradiated with 137Cs γ-rays up to 110 kGy, with 6 MeV mean energy neutron up to approximately 6 · 1014 n/cm2, with protons and mixed beam up to 1015 p/cm2. Results are presented for the effects on leakage currents and charge collection efficiencies for minimum ionizing electrons and alpha particles. The signal from minimum ionizing electrons was well separated from the noise even after the highest delivered exposures and the diodes are thus still operational as detectors. Saturation of the effects of radiation damage is observed in both the I-V characteristics and charge collection efficiency measurements. The requirements for detectors e.g. at present and planned hadron colliders is very high in terms of radiation hardness. Detectors for tracking applications close to the interaction point will receive charged particle doses in the range of 110 kGy and fast neutron fluences of 1014 n/cm2 during the lifetime of an experiment. In this thesis it is confirmed that GaAs detectors are radiation resistant to neutron irradiation for fluences up to 1015 n/cm2 and that GaAs detectors are feasible as inner trackers. Most of this work was performed in the framework of the RD8 collaboration at CERN.QC 20100920</p