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Kong Y.,ICx Technologies | Pausch G.,ICx Technologies | Roemer K.,ICx Technologies | Neuer M.,ICx Technologies | And 4 more authors.
IEEE Nuclear Science Symposium Conference Record | Year: 2010

A complete simulation framework that combines Monte Carlo simulation with the digital-signal-processing algorithms developed in-house is presented for designing and optimizing scintillation detector systems. The framework covers basic components of a practical scintillation detector system and includes all relevant physical processes. With the complete simulation individual physical factors that can affect the performance of a detector system, such as detector geometry, surface finishing, decay time and scintillation yield of scintillator as well as responses of photodetector and front-end electronics, can be taken into account. As a demonstration of the simulation framework, the light collections of plastic (EJ200), NaI(Tl) and BGO scintillators with different surface types have been simulated as a function of the reflectivity of a diffuse reflector. Optical simulations were further performed to investigate the homogeneity of light transportation and detection in plastic scintillators with different surface finishing properties and coupled to one or two PMT(s). Finally, detector signals simulated for a NaI(Tl) detector have been compared with measured mean pulses. The simulated signal can be further digitized and used as input of digital signal processing. © 2010 IEEE. Source

Bell Z.W.,Oak Ridge National Laboratory | Ziock K.-P.,Oak Ridge National Laboratory | Ohmes M.F.,ICx Radiation Inc. | Ohmes M.F.,Kansas State University | And 6 more authors.
IEEE Transactions on Nuclear Science | Year: 2010

We have performed measurements of neutron production from UF4 samples using liquid scintillator as the detector material. Neutrons and gamma rays were separated by a multichannel digital pulse shape discriminator, and the neutron pulse-height spectra were unfolded using sequential least-squares optimization with an active set strategy. The unfolded spectra were compared to estimates calculated with the SOURCES 4C code. © 2010 IEEE. Source

ICx Radiation Inc. | Date: 2010-08-05

A directional gamma radiation detector system for determining an angle under which a measured gamma radiation hits a gamma radiation detector system, includes gamma radiation detectors arranged in close distance; detector electronics for operating the at least two gamma radiation detectors as spectrometers in a way that the detector electronics are collecting energy spectra of the detected gamma rays for each gamma radiation detector; and system electronics allowing the directional gamma radiation detector system to identify coincident events in the at least two gamma radiation detectors.

Roy U.N.,ICx Radiation Inc. | Weiler S.,ICx Radiation Inc. | Stein J.,ICx Radiation Inc.
Journal of Crystal Growth | Year: 2010

Growth interface of large diameter CdZnTe ingots grown from Te solution by travelling heater method have been studied. Both macroscopic and microscopic investigations were carried out. The results indicated that the shape of the interface strongly governs the grain growth on the ingot, while the microscopic morphology of the growth interface is responsible for Te inclusions in the grown crystal. © 2010 Elsevier B.V. All rights reserved. Source

Gueorguiev A.,ICx Radiation Inc. | Preston J.,ICx Radiation Inc. | Hoy L.,ICx Radiation Inc. | Pausch G.,ICx Technologies | And 2 more authors.
IEEE Nuclear Science Symposium Conference Record | Year: 2010

ICx Radiation has developed a novel method to determine the direction of radiation with a device containing only two detectors by comparing and analyzing the paired-energy distributions of coincident events. The method does not require complex image reconstruction but rather extracts the directionality from the means and skewness of the two coincidence spectra. All energy data contribute to the energy spectrum, while events that occur within the coincidence time window are also added to a separate time-dependent buffer that represents the reduced spectra from each detector. These spectra contain counts only from true Compton events. The mean and skewness of each detector's reduced spectra subset is then calculated. Equal skewness and means correspond to the source being in front of the device. Opposite polarity skewness correspond to the source being located to the left or right of the device. For low count rates due to weak sources or sources located far away from the detectors, the skewness comparison gives fast indication for the hemisphere in which the source is located, while increased count rates or increased acquisition times reduce the uncertainties and allow a detailed angular detection of the source position. The simulations, experimental results and the angular resolution as a function of the strength, source energies and distance of the radiation source are discussed. © 2010 IEEE. Source

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