Title: EVALUATION OF THE BORON CONTENT IN FUEL PLATES FABRICATED FOR THE FIRST CORE LOADING OF THE ARMY SM-1 REACTOR (FORMERLY APPR-1)

Physics experinments were performed on the SM-1 (formerly APPR-1) core to evaluate temperature and pressure coefficients, transient xenon, neutron source requirements, safety margin, and core reactivity as a function of core life. The temperature coefficient was measured as --3.5 plus or minus 0.13 cents/ deg F at 443 deg F several times throughout life and no change with life time is thus far indicated. The hot to cold reactivity change (440 to 70 deg F) was 6.70 dollars. The pressure coefficient was 1.05 plus or minus 0.05 cents per 100 psi at 115 deg F. Reactivity value for equilibrium xenonmore » was found to be 3.32 dollars and peak xenon reactivity was 4.64 dollars. The 15 curie Po Be source and the beryllium photoneutron source have proved adequate for safe stantup. The safety margin 80% rod insertion'' was found to depend strongly upon the rod configuration. The core reactivity has decreased approximately 5.8 dollars up to 9.1 Mwyr leaving an estimated 5.6 dollars to be used. The core life is expected to be 15 Mwyr. All measurements indicated satisfactory performance of the (SM-1) core. (auth)« less