[2M07-09] Uncertainty, Covariance

[2M09] Estimation of covariance of neutron cross sections for decommissioning

*Tatsuki Amitani¹, Tsunenori Inakura¹, Naoki Yamano¹, Ken-ichi Tanaka², Chikako Ishizuka¹, Satoshi Chiba¹ (1. Tokyo Tech, 2. IAE)

Keywords:Decommissioning, Clearance, Uncertainty, Neutron cross section, Covariance, Bayesian Monte Carlo

Both reliable evaluations with calculation and measurement and appropriate estimation of uncertainty of those results are required to optimize conditioning and disposal of low-level radioactive waste generated from decommissioning, including the clearance materials. However, the uncertainty due to errors in cross-section data, which is one of the essential input data of the calculation, has never been estimated in the previous works. In this study, we estimated the covariances of neutron cross sections of nuclides which are important for decommissioning using a Bayesian Monte Carlo method based on the nuclear data evaluation code system T6.