Evaluation of dynamic nuclear reactor parameters through analysis of stochastic relationships.

Abstract

A theoretical probability distribution function for neutron triplet correlation that is amenable to experimental determination of the reactivity of a neutron multiplying system has been obtained. A two-dimensional data collection method designed for the experiment was implemented with the aid of an interface counting board installed in a microcomputer system. An efficient non-linear least-squares code was developed to fit experimental data to the theoretical distribution function to obtain reactivity. The system developed for data collection and analysis is fully portable, requiring only a microcomputer to implement. Reactivities obtained from measurements carried out on the University of Arizona Subcritical Assembly and the TRIGA Reactor were compared to results determined by other methods. The range of prompt reactivities measured is -34.2 dollars to -6.1 dollars.