[en] The central neutron spectrum of the Big Ten Critical Assembly, a cylindrical assembly with a 10 percent enriched uranium metal core surrounded by a depleted uranium metal reflector, has been measured between 32 keV and 1177 keV, using proton recoil proportional counting techniques. A cylindrical detector filled with hydrogen gas was used for measurements between 23 keV and 650 keV, and a methane filled detector was used between 228 keV and 2.6 MeV. Pulse shape discrimination techniques were used to separate proton recoil pulses from electron pulses resulting from γ-ray interactions below 200 keV. All of the measurements were performed with the assembly at a reactivity of 37 cents below delayed critical. The neutron spectrum was determined from the recoil proton data by response function unfolding. The monoenergetic neutron response functions and the high energy corrections to the data were computed using Monte Carlo methods. Monoenergetic neutron measurements were carried out at the LASL high current Van De Graaff and the Cockcroft--Walton Accelerator in order to test the accuracy of the computed response functions. The results of the spectrum measurements are compared with a transport theory computation of the neutron spectrum using E.N.D.F./B-III cross-section sets. (Diss. Abstr. Int., B)

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No abstract available

[en] The WOG-MERITS Program was established to improve the Technical Specifications for plants with nuclear steam supply systems designed by Westinghouse. Some of the areas targeted for improvement are technical content, bases content, organization and format. The MERITS program process methodology is based on a four phase program and utilizes a plant specific application. Phase I of the MERITS Program was completed in February 1987 and approved by the united States Nuclear Regulatory Commission (NRC) as an acceptable basis for proceeding with Phase II. The WOG-MERITS Working Group was formed to plan, manage, and staff the program. The MERITS program objectives are to: apply the AIF/NRC Policy Statement criteria to existing technical specifications and retain items that satisfy the criteria; to develop a preferred format and organization which considers human factor issues; to rewrite the technical specifications that are retained in a manner that improves the technical content and utilizes technical writing skills; to develop expanded bases; to develop options for controlling items removed from current technical specifications; to develop a writers guide for the preparation of technical specifications