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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.

The Neutron Induced Fission Fragment Tracking Experiment (NIFFTE) is a double-sided Time Projection Chamber (TPC) with micromegas readout designed to measure the energy-dependent neutron-induced fission cross sections of the major and minor actinides with unprecedented accuracy. The NIFFTE project addresses the challenge of minimizing major sources of systematic uncertainties from previous fission chamber measurements such as: target and beam non-uniformities, misidentification of alpha and light charged particles as fission fragments, and uncertainties inherent to the reference standards used. In-beam tests of the NIFFTE TPC at the Los Alamos Neutron Science Center (LANSCE) started in 2010 and have continued in 2011, 2012 and 2013. An overview of the NIFFTE TPC status and performance at LANSCE will be presented., Comment: Prepared for JINST as proceeding of the MPGD13 Conference