THE FRENCH "CEA 86" MULTIGROUP CROSS-SECTION LIBRARY AND ITS INTEGRAL QUALIFICATION


Alain SANTAMARINA

CEA - IRDI/DEDR
CADARACHE, Bât. 242, 13108 St PAUL-LEZ-DURANCE CEDEX, FRANCE


Henry TELLIER

CEA - IRDI/DEDR
SACLAY, 91191 GIF-SUR-YVETTE, FRANCE


This paper describe the up-dated 99 groups library of the APOLLO French neutron computer code, the denominated "CEA 86" library. The multigroup cross-section sets are based on the more recent nuclear data evaluations. The THEMIS code was generally used for the JEF-1 processing. In order to account for recent differential measurements and to improve the consistency between calculation and integral experiments, we produced our own CEA evaluations for the actinide nuclides: 235U, 238U, 239Pu, 240Pu, 241Am. This new APOLLO library was checked against critical experiments and PWR measurements: computed Conversion Factor, Reactivity Coefficients, Multiplication Factor, and Pu build-up are now in good agreement with LWR experimental results. PWR Pu recycling calculations, as does as HCLWR design studies, are also significantly improved.

KEYWORDS: APOLLO Multigroup Library, JEF-1 file, CEA Evaluation, Integral Experiments