FORMULATION OF DATA SYNTHESIS TECHNIQUE FOR FEYNMAN-ALPHA METHOD

We intend to develop a subcriticality monitor based on the Feynman-a m ethod, which detects a change in the prompt neutron decay constant cau sed by a change in the reactivity of a system containing nuclear fuel materials. For the practical use of this method, quick data processing is necessary to facilitate a real time measurement and it needs to be applicable to a wide range of count rates in the neutron detector. Th e Feynman-alpha method, based on pulse counting, has a serious problem relating to the counting statistics, namely the count loss effect due to the dead time of counter itself and the following counting circuit . To eliminate the count loss effect, especially in a high count rate region, a quick correction technique should be established to ensure a ccurate measurement. As a candidate for this, we have developed the da ta-synthesis technique which processes synthesized data generated by a dding multiple time-series data acquired by independent neutron detect ors. The present paper provides the derivation of a formula for this d ata-synthesis technique and the result of a numerical examination on i ts applicability. (C) 1997 Elsevier Science Ltd.