Neutron detection by superconducting tunnel junctions on a Li2B4O7 single-crystal absorber
Neutron detection by superconducting tunnel junctions on a Li2B4O7 single-crystal absorber
复制标题
Li2B4O7 单晶吸收体上的超导隧道结检测中子
DOI：
10.1016/j.nima.2003.11.222
复制
发表时间：
2004
影响因子：
1.4
通讯作者：
M. Ohkubo
中科院分区：
文献类型：
--
作者：
Tatsuya Nakamura;M. Katagiri;M. Ukibe;T. Ikeuchi;M. Ohkubo
我们成功地利用在 Li2B4O7 单晶上制造的超导隧道结 (STJ) 探测中子。中子通过核反应6Li+n→T+α+4.78MeV和10B+n→7Li+α+2.3MeV被捕获在晶体中，在衬底中激发大量声子。声子在吸收器中传播并由 STJ 进行测量。我们选择Li2B4O7单晶作为吸收材料，因为6Li和10B具有大的中子截面、低γ射线敏感性、衬底中的粒子射程短和声子速度快等特性。晶体上串联或多个STJ将实现二维中子成像，具有高探测效率、低γ射线背景和几微米的高空间分辨率。在本文中，我们演示了 STJ 的中子探测，并报告了所制造的 STJ 的基本特征，包括它们的 X 射线响应和中子探测。相距 ∼1.3mm 的两个结点之间脉冲高度的相关性清楚地表明了中子成像的可能性。
We succeeded in detecting neutrons using superconducting tunnel junctions (STJs) fabricated on a single crystal of Li2B4O7. Neutrons are captured in the crystal by the nuclear reactions6Li+n→T+alpha+4.78MeV and10B+n→7Li+alpha+2.3MeV, which excite a large number of phonons in the substrate. The phonons propagate in the absorber and are measured by the STJs. We selected a single crystal of Li2B4O7as the absorber material because of properties such as the large neutron cross-section of6Li and10B, low γ-ray sensitivity, short particle range in the substrate, and fast phonon velocity. Series-connected or multiple STJs on the crystal would enable two-dimensional neutron imaging with high detection efficiency, low γ-ray background, and a high spatial resolution of a few microns. In this paper, we demonstrate neutron detection by STJs and report the basic characteristics of the fabricated STJs, including their X-ray response and neutron detection. The correlation in pulse heights between two junctions located ∼1.3mm apart clearly indicates the possibility of neutron imaging.