中文摘要：

目前，有大量的实验研究电子、中子、原子和分子的衍射现象，而且这些实验有各种各样的理论解释。在本文中，我们首次对低能氦核的单缝衍射问题给出了一种新的量子力学研究方法。通过研究我们得到一些新的结果：当单缝宽度a在3λ≤α≤60λ时有明显的衍射现象；单缝长度主要影响条纹的衍射强度；氦核能量也只影响条纹的衍射强度；而单缝厚度对条纹强度及条纹形状都有一定影响。相信所有这些新的预言在氦核单缝衍射实验中能得到验证。

英文摘要：

Phenomena of electron, neutron, atomic and molecular diffraction have been researched by many experiments throughout the last year and these experiments are explained by various theory. In this paper, we study the single-slit diffraction of 4 He with a new approach of quantum mechanics at first. We find some new results.. Both the shape of single-slit and the energy of neutron have affect the diffraction pattern. The obvious diffraction phenomenon can be obtained when the single-slit width a is in the range of 3λ≤α≤60λ. The length of the single-slit affects the diffraction intensity and the thickness not only affects the intensity, but also changes the diffraction patterns. The energy of 4 He only affect the intensity. Those effect predicted in our work can be tested by the ^4 He single-slit diffraction experiment.