Neutronics diagnostics for European ITER TBMs: Activation foil spectrometer for short measurement cycles
Neutronics diagnostics for European ITER TBMs: Activation foil spectrometer for short measurement cycles
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欧洲 ITER TBM 的中子学诊断：用于短测量周期的活化箔光谱仪
DOI：
10.1016/j.fusengdes.2012.02.129
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发表时间：
2012
影响因子：
1.7
通讯作者：
I. Rovni
中科院分区：
文献类型：
--
作者：
A. Klix;A. Domula;U. Fischer;D. Gehre;P. Pereslavtsev;I. Rovni
ITER中子学试验包层模块（TBM）实验的一个重要目的是检查在比现有设施更接近未来聚变动力反应堆的环境中核反应的预测准确性。欧洲原子能共同体最近支持的几个研发项目都在研究适合于ITER TBM恶劣环境的测量方法。在这一框架内，韩国科学技术研究所正在开发一种活化箔能谱仪，用于测量隧道掘进机中的局部中子通量密度。我们打算建立一种测量方法，它允许记录在小包装的活化箔的诱导活动，同时计算相应的光谱中子通量密度与中等时间分辨率的几十秒后立即从TBM提取。在目前的工作中，我们提出了一套候选的激活箔材料，覆盖从热到14MeV的中子能量范围。为了评估其基本适用性，这样的测量，我们已经计算了诱导伽马射线活动的箔使用计算的中子能谱在欧洲HCPB隧道掘进机的代表性的位置，假设一个短的照射时间为30秒。在进一步的步骤中，我们已经调查了脉冲高度谱，这将是在一个典型的伽马射线测量安排中获得的HPGe探测器，并得出结论，所提出的一套激活箔应该基本上是适合这样的测量系统，但需要改善相关的横截面的不确定性。
An important aim of neutronics Test Blanket Module (TBM) experiments in ITER will be to check the prediction accuracy of nuclear responses in an environment closer to a future fusion power reactor than so far provided by existing facilities. The development of measurement methods suitable for the harsh environment in an ITER TBM has been addressed in several recent R&D programs supported by Euratom. Within this framework, KIT is developing an activation foil spectrometer for the measurement of local neutron flux densities in the TBM. We intend to establish a measurement method which allows to record the induced activities in small packages of activation foils simultaneously and to calculate the corresponding spectral neutron flux densities with moderate time resolution of tens of seconds immediately after extraction from the TBM. In the present work we propose a candidate set of activation foil materials which cover the neutron energy range from thermal to 14MeV. In order to assess their basic suitability for such measurements, we have computed induced gamma-ray activities in the foils using a calculated neutron spectrum in a representative position in the European HCPB TBM assuming a short irradiation time of 30s. In a further step we have investigated pulse height spectra which would be obtained in a typical gamma-ray measurement arrangement in a HPGe detector and concluded that the proposed set of activation foils should be basically suitable for such a measurement system but require improvement of relevant cross sections uncertainties.