Determination of Subcritical Reactivity of a Thermal Accelerator-Driven System from Beam Trip and Restart Experiment

作者：Taninaka Hiroshi; Hashimoto Kengo^*; Pyeon Cheol Ho; Sano Tadafumi; Misawa Tsuyoshi; Unesaki Hironobu; Sugiyama Wataru; Ohsawa Takaaki

来源：Journal of Nuclear Science and Technology, 2011, 48(6): 873-879.

DOI：10.1080/18811248.2011.9711772

• ADS
• KUCA
• thermal neutron spectrum
• subcriticality
• beam trip
• beam restart
• least squares
• inverse kinetics method

An experimental technique based on an accelerator-beam trip or restart operation is proposed to determine the subcritical reactivity of an accelerator-driven system (ADS). Applying the least-squares inverse kinetics method to the data analysis, the subcriticality can be inferred from time-sequence neutron count data after these operations. A series of beam trip and restart experiments with 14 MeV neutrons were carried out in a thermal ADS of Kyoto University Critical Assembly (KUCA), to demonstrate the applicability of the proposed technique. The subcriticalities evaluated using neutron counters far from the DT target were consistent with those obtained in a previous pulsed neutron experiment. However, a counter placed close to the target significantly overestimated the subcriticality. The present technique is expected to be available for subcriritcality measurement at startup and shutdown of various ADSs.

• 出版日期2011-6