Uzan Lior, Leão Juscelino B, Brocker Christoph, Mattes Daniel, Dax Tanya
Nuclear Research Center Negev, Israel.
NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, MD, 20899, USA.
J Neutron Res. 2020;22(4). doi: 10.3233/jnr-200173.
A newly developed polychromatic beam neutron reflectometer CANDOR (Chromatic Analysis Neutron Diffractometer Or Reflectometer) on NG-1 at the NIST Center for Neutron research (NCNR) utilizes a wavelength-sensitive neutron detector consisting of 324 analyzing highly-oriented pyrolytic graphite (HOPG) crystals positioned sequentially in rows. Known for having a small thermal diffuse scattering cross section, HOPG crystals can lead to low signal-to-noise ratios in wavelength-sensitive detectors such as CANDOR. Even though it is possible to mathematically separate the desired signal from thermal diffuse scattering; by cooling the detector array of HOPG crystals in order to minimize the Debye Waller effect generates a better solution to this problem. In this heat transfer analysis study we show, within the instrument design constrains and thermodynamic considerations, technical feasibility and test results for the development of the New Polychromatic Beam Neutron Reflectometer CANDOR (Chromatic Analysis Neutron Diffractometer Or Reflectometer) at the NIST Center for Neutron Research.
美国国家标准与技术研究院中子研究中心（NCNR）的NG-1上一台新开发的多色束中子反射仪CANDOR（彩色分析中子衍射仪或反射仪），使用了一种波长敏感型中子探测器，该探测器由324块高度取向热解石墨（HOPG）晶体依次排成行组成。HOPG晶体以热漫散射截面小而闻名，但在像CANDOR这样的波长敏感型探测器中会导致低信噪比。尽管可以通过数学方法从热漫散射中分离出所需信号，但通过冷却HOPG晶体探测器阵列以最小化德拜-瓦勒效应，能更好地解决这个问题。在本传热分析研究中，我们展示了在仪器设计约束和热力学考量范围内，美国国家标准与技术研究院中子研究中心开发新型多色束中子反射仪CANDOR（彩色分析中子衍射仪或反射仪）的技术可行性和测试结果。
