Nuclear data are the main uncertainty sources for modern neutron transport calculations. However, complete correlation matrices among different nuclear data are not presented in the current evaluations. In order to completely consider that correlation between nuclear data, the present work propagates the covariance matrix of continuum n+⁵⁶Fe reaction model parameters to the effective neutron multiplication factor (k_eff) of a thermal neutron spectrum benchmark and a fast neutron spectrum benchmark. Results show that the uncertainty propagated from angular distribution is not negligible. The general correlations between angular distributions and cross sections of ⁵⁶Fe for neutron energies above 850 keV are respectively −0.39 ± 0.05 and −1.02 ± 0.02 for k_eff calculation in the thermal and fast benchmarks, respectively. These correlations reveal the importance of a complete correlation matrix of nuclear data for propagating uncertainties to neutronic calculations.

核数据是现代中子输运计算的主要不确定性来源。然而，目前的评估中没有呈现不同核数据之间的完整相关矩阵。为了充分考虑核数据之间的相关性，本工作将连续 n+ ⁵⁶ Fe 反应模型参数的协方差矩阵传播到热中子谱基准和快中子谱基准的有效中子倍增因子 ( k _eff )。结果表明，从角分布传播的不确定性是不可忽略的。角分布与截面的一般相关性⁵⁶对于 850 keV 以上的中子能量，对于热基准和快速基准中的k _eff计算，Fe 分别为 -0.39 ± 0.05 和 -1.02 ± 0.02 。这些相关性揭示了核数据的完整相关矩阵对于将不确定性传播到中子计算的重要性。