The reliable detection of neutrons in a harsh gamma-ray environment is an important aspect of establishing non-destructive methods for the characterization of spent nuclear fuel. In this study, we present results from extended in-situ monitoring of detector systems consisting of commercially available components: EJ-426, a $^6$Li-enriched solid-state scintillator material sensitive to thermal neutrons, and two different types of Hamamatsu photomultiplier tubes (PMT). Over the period of eight months, these detectors were operated in close vicinity to spent nuclear fuel stored at the interim storage facility CLAB, Oskarshamn, Sweden. At the measurement position the detectors were continuously exposed to an estimated neutron flux of approx. 280 n/s $\cdot$ cm$^2$ and a gamma-ray dose rate of approx. 6 Sv/h.
Using offline software algorithms, neutron pulses were identified in the data. Over the entire investigated dose range of up to 35 kGr, the detector systems were functioning and were delivering detectable neutron signals. Their performance as measured by the number of identified neutrons degrades down to about 30% of the initial value. Investigations of the irradiated components suggest that this degradation is a result of reduced optical transparency of the involved materials as well as a reduction of PMT gain due to the continuous high currents. Increasing the gain of the PMT through step-ups of the applied high voltage allowed to partially compensate for this loss in detection sensitivity.
The integrated neutron fluence during the measurement was experimentally verified to be in the order of $5 \cdot 10^9$ n/cm$^2$. The results were interpreted with the help of MCNP6.2 simulations of the setup and the neutron flux.
Detection of ultracold neutrons with powdered scintillator screens
Los Alamos National Laboratory（洛斯阿拉莫斯国家实验室）；North Carolina State University（北卡罗来纳州立大学）；Tennessee Technological University（田纳西理工大学）；University of Illinois（伊利诺伊大学）；East Tennessee State University（东田纳西州立大学）；New Mexico State University（新墨西哥州立大学）
High Temporal and Spatial Resolution X-Ray and Gamma-Ray Imaging using an Event-Mode Scintillator-Based Detector
Forschungs-Neutronenquelle Heinz Maier-Leibnitz, Technical University of Munich（海因茨·迈尔-莱布尼茨研究用中子源，慕尼黑工业大学）；Crytur, Ltd.（Crytur有限公司）；Chair of Biomedical Physics, Technical University of Munich（慕尼黑工业大学生物物理系）；Czech Technical University（捷克理工大学）；Institute of Physics of Czech Academy of Sciences（捷克科学院物理研究所）；Florida International University（佛罗里达国际大学）
Gamma Rossi-alpha, Feynman-alpha and Gamma Differential Die-Away concepts as a potential alternative/complement to the traditional thermal neutron based analysis in Safeguards
本文提出了一种基于热中子相关和多重数测量的新概念。该概念的主要思想包括使用源自1H（n，gamma）2D反应的2.223 MeV伽马（或1.201 MeV，DE），而不是使用传统的热中子计数。本文的研究结果表明，热中子俘获反应产生的γ射线在同一时间尺度上保留了热（快）中子的相关特性信息。因此，代替热中子探测器（或作为补充），可以使用传统且廉价的伽马探测器，诸如NaI、BGO、CdZnTe或任何其他伽马探测器。在这项工作中，我们使用D8 × 8 cm 2碘化钠闪烁体来测试的概念。因此，新方法有助于解决更换3 He计数器的问题以及与直接在乏燃料池中的乏核燃料的具体测量有关的问题。它对核保障和核安全特别重要。总的来说，这项工作代表了概念研究的证明，并报告了热中子俘获伽玛可用于相关性和多重性测量的实验和数值证据。对252 Cf相关中子源和241 Am-Be随机中子源进行了研究。本文还对Gamma微分消失方法的相关思想进行了数值研究，并将在未来的工作中进行实验验证。
Automated crystal orientation mapping by precession electron diffraction assisted four-dimensional scanning transmission electron microscopy (4D-STEM) using a scintillator based CMOS detector
Final assessment of radioactive impurities in the JUNO detector
IPHC, Université de Strasbourg, CNRS/IN2P3（斯特拉斯堡大学）；Sun Yat-Sen University（中山大学）；The University of Liverpool（利物浦大学）；INFN Catania and Dipartimento di Fisica e Astronomia dell Università di Catania（意大利国家核物理研究所卡塔尼亚分部及卡塔尼亚大学物理与天文系）；Joint Institute for Nuclear Research（苏联联合核研究所）；INFN Sezione di Milano and Dipartimento di Fisica dell Università di Milano（意大利国家核物理研究所米兰分部及米兰大学物理系）；IJCLab, Université Paris-Saclay, CNRS/IN2P3（巴黎萨克雷大学）；INFN Milano Bicocca and University of Milano Bicocca（意大利国家核物理研究所米拉诺比科卡分部及米拉诺比科卡大学）；INFN Sezione di Padova（意大利国家核物理研究所帕多瓦分部）
