Lacoste V, Reginatto M, Asselineau B, Muller H
Institut de Radioprotection et de Sûreté Nucléaire, BP 3, F-13115 Saint-Paul-lez-Durance, France.
Radiat Prot Dosimetry. 2007;125(1-4):304-8. doi: 10.1093/rpd/ncm161. Epub 2007 Feb 27.
The Institute for Radiological protection and Nuclear Safety was engaged in the EC funded EVIDOS project to provide reference spectrometry data using its Bonner sphere system. The data were processed by means of two unfolding codes, NUBAY and GRAVEL, both provided by the Physikalisch-Technische Bundesanstalt. The NUBAY program, based on Bayesian parameter estimation methods, assumes a parameterised spectrum and provides posterior probability distributions for the parameters. The code GRAVEL, an iterative algorithm based on SAND-II, was used with various default spectra, among them the NUBAY solution. The BS measurements were used to establish the neutron fluence energy distributions and reference values for the neutron ambient dose equivalent. As this quantity depends strongly on the high energy neutrons, a sensitivity analysis was done by unfolding the BS data with GRAVEL using the NUBAY solution spectrum as default with various changes in the parameters of the high energy peak. This new method of analysing Bonner sphere data allowed the determination of reliable neutron spectra, as well as a very good estimate of the corresponding integral quantities with small associated uncertainties.
辐射防护与核安全研究所参与了由欧盟资助的EVIDOS项目，以利用其邦纳球系统提供参考能谱数据。这些数据通过两种解谱代码NUBAY和GRAVEL进行处理，这两种代码均由德国物理技术研究院提供。基于贝叶斯参数估计方法的NUBAY程序假定有一个参数化谱，并为参数提供后验概率分布。代码GRAVEL是一种基于SAND-II的迭代算法，与各种默认谱一起使用，其中包括NUBAY解。邦纳球测量用于确定中子注量能量分布和中子周围剂量当量的参考值。由于该量强烈依赖于高能中子，因此通过使用GRAVEL解谱邦纳球数据进行了灵敏度分析，默认使用NUBAY解谱，并对高能峰的参数进行各种变化。这种分析邦纳球数据的新方法能够确定可靠的中子谱，并以较小的相关不确定性对相应的积分量进行很好的估计。
