New approaches to provide feedback from nuclear and covariance data adjustment for effective improvement of evaluated nuclear data files

¹ Idaho National Laboratory, 2525 Fremont Ave., PO Box 1625, Idaho Falls, ID 83415-3860, USA
² Paul Scherrer Institut, Würenlingen, Switzerland
³ Jožef Stefan Institute, Ljubljana, Slovenia
⁴ Karlsruhe Institute of Technology, Karlsruhe, Germany

^a e-mail: Giuseppe.Palmiotti@inl.gov

Published online: 13 September 2017

Abstract

A critical examination of the role of uncertainty assessment, target accuracies, role of integral experiment for validation and, consequently, of data adjustments methods is underway since several years at OECD-NEA, the objective being to provide criteria and practical approaches to use effectively the results of sensitivity analyses and cross section adjustments for feedback to evaluators and experimentalists in order to improve without ambiguities the knowledge of neutron cross sections, uncertainties, and correlations to be used in a wide range of applications and to meet new requirements and constraints for innovative reactor and fuel cycle system design. An approach will be described that expands as much as possible the use in the adjustment procedure of selected integral experiments that provide information on “elementary” phenomena, on separated individual physics effects related to specific isotopes or on specific energy ranges. An application to a large experimental data base has been performed and the results are discussed in the perspective of new evaluation projects like the CIELO initiative.