论文标题
高精度,高分辨率235U(n,f)横截面,从n_tof(cern)的热量到10 keV能量范围
High accuracy, high resolution 235U(n,f) cross section from n_TOF (CERN) in the thermal to 10 keV energy range
论文作者
论文摘要
相对于6LI(N,T)和10B(N,T)和10B(N,Alpha)标准反应的N_TOF设施的235U(N,F)横截面的测量在N_TOF设施的宽能范围(25 MeV -170 KEV)中,具有高分辨率和准确性,具有高分辨率和准确性,具有基于六个样本和六个Silicon Detectors的堆栈的设置。在本文中,我们报告了热和10 KEV中子能量之间的结果。 SAMMY代码与代码进行了共振分析,最多进行了200 eV。将所得的裂变核与根据最新主要评估数据库的共振参数提取的裂变内核进行比较。在适当选择的宽度的能量组中,还对N_TOF数据与评估的横截面进行了比较,从热量到10 keV中子能量。在新结果与最新评估的数据文件ENDF-B/VIII和JEFF-3.3之间以及与IAEA参考文件之间的平均协议。但是,在某些特定的能源区域中仍然存在一些差异。这里介绍的新数据集以前所未有的分辨率和准确性为特征,可以帮助改善已解决的分辨率区域的评估和最多10 keV,并减少影响该地区的不确定性。
The 235U(n,f) cross section was measured in a wide energy range (25 meV - 170 keV) at the n_TOF facility at CERN, relative to 6Li(n,t) and 10B(n,alpha) standard reactions, with high resolution and accuracy, with a setup based on a stack of six samples and six silicon detectors placed in the neutron beam. In this paper we report on the results in the region between thermal and 10 keV neutron energy. A resonance analysis has been performed up to 200 eV, with the code SAMMY. The resulting fission kernels are compared with the ones extracted on the basis of the resonance parameters of the most recent major evaluated data libraries. A comparison of the n_TOF data with the evaluated cross sections is also performed from thermal to 10 keV neutron energy for the energy-averaged cross section in energy groups of suitably chosen width. A good agreement is found in average between the new results and the latest evaluated data files ENDF-B/VIII and JEFF-3.3, as well as with respect to the IAEA reference files. However, some discrepancies are still present in some specific energy regions. The new dataset here presented, characterized by unprecedented resolution and accuracy, can help improving the evaluations in the Resolved Resonance Region and up to 10 keV, and reduce the uncertainties that affect this region.