Research on Correction of Background and Neutron Source in Measurement of Reactivity

In the measurement of reactivity, disturbance currents such as γ background, electrical noise and neutron source currents take a significant fraction in the measured signal, resulting in a large error to the measured reactivity. In this paper, the impacts of background and source currents on the reactivity measurement were described, and the dual fitting method, a self-developed method on the correction of background and source currents, was introduced. The method was used in the dynamic rod worth measurements in a test reactor and satisfactory results were obtained.