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The various technologies presented herein relate to detecting nuclear material at a large stand-off distance. An imaging system is presented which can detect nuclear material by utilizing time encoded imaging relating to maximum and minimum radiation particle counts rates. The imaging system is integrated with a data acquisition system that can utilize variations in photon pulse shape to discriminate between neutron and gamma-ray interactions. Modulation in the detected neutron count rates as a function of the angular orientation of the detector due to attenuation of neighboring detectors is utilized to reconstruct the neutron source distribution over 360 degrees around the imaging system. Neutrons (e.g., fast neutrons) and/or gamma-rays are incident upon scintillation material in the imager, the photons generated by the scintillation material are converted to electrical energy from which the respective neutrons/gamma rays can be determined and, accordingly, a direction to, and the location of, a radiation source identified.

The existing pixel tracking detectors of ATLAS and CMS experiments will have to be replaced after LHC luminosity upgrade (super-LHC or sLHC), due to increased radiation level and tracking performance requirements. We are studying device active area re-optimization by cutting away dead area and some of the guard rings of existing sensors. Performance of the cut sensors will be described. We also present a feasibility study of operating irradiated silicon sensors after extreme temperature excursion characteristic of a standard bump-bonding process. This is relevant for high dose radiation studies before a sLHC-quality readout ASIC is developed.