We report a simple technique for direct neutron spectroscopy using pure LaCl₃ crystals. Pure LaCl₃ crystals exhibit considerably better pulse shape discrimination (PSD) capabilities with relatively good energy resolution as compared with Ce-doped LaCl₃ crystals. Single crystals of pure and Ce-doped LaCl₃ were grown using an inhouse-developed Bridgman furnace. PSD capabilities of these crystals were investigated using ²⁴¹Am and ¹³⁷Cs sources. Fast neutron detection was tested using a²⁵²Cf source and three separate bands corresponding to electron, proton, and alpha were observed. The proton band induced by the ³⁵Cl(n,p)³⁵S reaction can be used for direct neutron spectroscopy because proton energy is proportional to incident neutron energy. Owing to good scintillation performance and excellent PSD capabilities, pure LaCl₃ is a promising candidate for space detectors and other applications that necessitate gamma/fast neutron discrimination capability.

我们报告了一种使用纯 LaCl ₃晶体进行直接中子光谱的简单技术。与掺杂 Ce 的 LaCl ₃晶体相比，纯的 LaCl ₃晶体表现出明显更好的脉冲形状鉴别 (PSD) 能力和相对较好的能量分辨率。使用内部开发的布里奇曼炉生长纯和 Ce 掺杂的 LaCl ₃单晶。使用²⁴¹ Am 和¹³⁷ Cs 源研究了这些晶体的 PSD 能力。使用²⁵² Cf 源对快速中子检测进行了测试，并观察到了对应于电子、质子和 α 的三个独立波段。由³⁵ Cl(n,p)诱导的质子带³⁵ S 反应可用于直接中子光谱，因为质子能量与入射中子能量成正比。由于良好的闪烁性能和出色的 PSD 能力，纯 LaCl ₃是空间探测器和其他需要伽马/快中子鉴别能力的应用的有希望的候选者。