大学物理 ›› 2019, Vol. 38 ›› Issue (12): 10-.doi: 10.16854 /j.cnki.1000-0712.190055

• 教学研究 • 上一篇    下一篇

关于带电粒子在磁单极场中运动的一些评注

林琼桂   

  1. 中山大学物理学院,广东广州510275
  • 收稿日期:2019-02-18 修回日期:2019-06-25 出版日期:2019-12-20 发布日期:2020-01-22
  • 作者简介:林琼桂( 1963—) ,男,广东潮阳人,中山大学物理学院教授,博士生导师,从事理论物理学的教学和研究工作.
  • 基金资助:
    中山大学教务部2018 年度教学质量工程类项目( 中大教务2018 年294 号) 资助

Some notes on the motion of a charged particle in the field of a magnetic monopole

LIN Qiong-gui   

  1. School of Physics,SunYat-Sen University,Guangzhou,Guangdong 510275,China
  • Received:2019-02-18 Revised:2019-06-25 Online:2019-12-20 Published:2020-01-22

摘要:

指出教科书中关于带电粒子在磁单极场中的散射与电荷量子化的简化讨论存在明显的错误.通过对运动轨迹的仔细分析,得出的物理图像是: 粒子从入射到出射,极距角θ 和方位角均发生了变化.特别是,当瞄准距离很大时, 的变化近似为±π/2.计算了角动量的变化并得到了合理的结果.顺便讨论了散射截面的计算.

关键词: 磁单极场, 带电粒子的运动, 方位角变化, 角动量变化, 散射截面

Abstract:

We point out that the simplified calculations in the textbook on the scattering of charged particles by the field of a magnetic monopole and the quantization of electric charge lead to some obvious error. Reexamination of the orbit of the charged particle yields the physical picture: the azimuthal angle  as well as the polar angle θ of the incident particle change after scattering. In particular,for very large impact parameter,the change of  is approximately ±π/2. The change of the angular momentum is calculated and reasonable results are obtained. The scattering cross section is also discussed.

Key words: magnetic monopole field, motion of charged particles, change of azimuthal angle, change of angular momentum, scattering cross section