Relative coincidence counts per gram of effective • Pu vs the PuOsample mass. The upper and lower curves show the data before and after correction for multiplication, respectively. (From ref. 35). ZPPR drawer containing two rows of plutonium plates interspersed with plates of depleted uranium, sodium, aluminum, carbon, and iron to mock up structure and coolant materials in a fast critical assembly. (From ref. 28.) Measurement setup for a ZPPR drawer, showing the HLNCC for neutron coincidence counting and the IAEA intrinsic germanium detector with its collimator for measurement of plutonium gamma-ray line ratios. (From ref. 28.) Axial coincidence efficiency for the two-position count to obtain a uniform sum over an extended region (40 cm). (From ref. 24.) Mixed-oxide BWR fuel-rod assembly mockup for measurement with the HLNCC. (From ref. 25.) Coincidence response measured with the HLNCC vs number of fuel rods in a PuO 2-UO 2 fuel assembly mockup. (From ref. 25.

This report summarizes and evaluates field tests of the Active Well Coincidence Counter (AWCC) at Winfrith and Dounreay, United Kingdom. The applicability of the AWCC for assaying the uranium content of a wide variety of materials was demonstrated and calibration curves were generated. The AWCC was used in three modes (fastj thermal, and passive) while assaying powders, pellets, cartridges, plates, assorted residues, and materials-testing-reactor fuel assemblies.

Abstruc#-MOSFETswith 70-110A thick furnace N20-annealed gate oxides are examined at both room and liquid nitrogen temperatures. The N 2 0 anneal not only improves device performance, e.g. by increasing the high normal field mobility and current drivability, but it also suppresses degradation induced by Fowler-Nordheim and channel hot-carrier injection. Random telegraph noise measurements reveal a possible correlation between the interface properties and the mobility. OPM 95lPcmW m J W

T he active well coincidence counter (AWCC) was calibrated at the Chalk River Nuclear Laboratories (CRNL) for the assay of 93%-enriched fuel materials in three categories: (1) uranium-aluminum billets, (2) uranium-aluminum fuel elements, and (3) uranium metal pieces. The AWCC was a standard instrument supplied to the International Atomic Energy Agency under the International Safeguards Project Office Task A.51. Excellent agreement was obtained between the CRNL measurements and previous Los Alamos National Laboratory measurements on similar mockup fuel material. Calibration curves were obtained for each sample category.

A multiplicity sorter for the latest Los Alamos National Laboratory version of shift-register coincidence electronics is described. The multiplicity information taken from the coincidence-gate up-down counter is decoded and gated onto the output lines by prompt real-plus-accidental (R+A) and delayed accidental (A) strobes. Multiplicities of 0-7 and >B are sorted for both the P+A and A aates. I.