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A comprehensive comparison of the dominant sources of radiation-induced blur for radiographic imaging system performance is made. End-point energies of 6, 10, 15, and 20 MeV bremsstrahlung photon radiation produced at the Los Alamos National Laboratory Microtron facility were used to examine the performance of large-panel cerium-doped lutetium yttrium silicon oxide (LYSO:Ce) scintillators 3, 5 and 10 mm thick. The system resolution was measured and compared between the various end-point energies and scintillator thicknesses. Contrary to expectations, it is found that there was only a minor dependence of system resolution on scintillator thickness or beam end-point energy. This indicates that increased scintillator thickness does not have a dramatic effect on system performance. The data are then compared to Geant4 simulations to assess contributions to the system performance through the examination of modulation transfer functions. It was determined that the low-frequency response of the system is dominated by the radiation-induced signal, while the higher-frequency response of the system is dominated by the optical imaging of the scintillation emission.

A digital data acquisition system has been combined with a double Frisch gridded ionization chamber for use at both moderated and unmoderated neutron sources at the Los Alamos Neutron Science (LANSCE) facility. The high efficiency of the instrument combined with intense LANSCE beams and new acquisition system permits fission output measurements across 11 orders of magnitude incident neutron energy. The acquisition and analysis system is presented along with the first in-beam performance tests of the setup.

The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) collaboration is developing a Time Projection Chamber (TPC) to measure neutron-induced fission cross sections with unprecedented accuracy. Modifying TPC technology for nuclear physics applications is a challenging endeavor, and frequent testing and evaluation is required to ensure that all components are behaving as expected. In-beam tests of the NIFFTE TPC at the Los Alamos Neutron Science Center (LAN-SCE) commenced in 2010. An overview of the NIFFTE TPC experiments performed at LANSCE will be presented, along with preliminary performance results.

A fission TPC is being developed to measure the energy-dependent neutron induced fission cross sections of the major and minor actinides to an accuracy of better than 1%. Achieving such an accuracy will depend in part, on the ability of the TPC to provide precise tracking and identification of charged particles. A measurement of the α -decay to spontaneous fission branching ratio of 252 Cf used to benchmark the performance of the TPC will be discussed.

The NIFFTE collaboration has developed a time projection chamber to study neutron-induced fission events in actinide targets by tracking and identifying fission fragments in three dimensions as they traverse a gas volume. This paper will provide an overview of the analysis software that has been developed by the NIFFTE collaboration, as well as examples of its success in analyzing data.

When fully instrumented, the NIFFTE Time Projection Chamber will consist of nearly 6000 channels, each of which requires a preamplifier, ADC, and digital readout. To minimize channel cost and size, the EtherDAQ data acquisition system utilizes off-the-shelf FPGA and Ethernet fiber technology. This application of commercially-available components made it possible to meet the requirements of the DAQ system with considerably less development cost and time than the a customized ASIC solution, and provides considerable flexibility in the final design. The detailed design and current status of the preamplifier and EtherDAQ boards will be discussed.

The general properties needed in targets (sources) for high precision, high accuracy measurements are reviewed. The application of these principles to the problem of developing targets for the Fission TPC is described. Longer term issues, such as the availability of actinide materials, improved knowledge of energy losses and straggling and the stability of targets during irradiation are also discussed.