Study of axis-symmetry for judgement on nuclear parts

In this paper, gamma-ray distributions from nuclear weapon parts of different shapes are simulated. The gamma-rays from a cylinder nuclear part have axis-symmetry distribution, while the gamma-rays from prism nuclear parts are of asymmetry distribution. The quadra- and penta-prism distributions differ obviously from that of the cylinder. However, the asymmetry of hexa-, octo- and dodeca-prism reduces gradually to approach to the symmetry distribution of the cylinder. (authors)