An undergraduate-level student experiment has been designed and implemented to measure the forward–backward asymmetry of the decay of the cosmic-ray muons, offering a pedagogical view to the parity violation in weak interactions. The detector system consists of six plastic scintillators installed vertically in row. The backward–forward asymmetry of the decay e⁻ and e⁺ with respect to the muon motion direction is correlated with the incident depth of the muon stopped in the scintillator. MC simulations have been carried out in order to better interpret the data and optimize the data analysis. The forward–backward asymmetry of 0.051 0.027 is deduced for the decay of cosmic-ray muons in the energy range being studied. The results are consistent with the picture of parity violation in weak interactions. The experiment can be constructed by the senior undergraduate students under the guidance of the course teacher.

设计并实施了一个本科生级学生实验，以测量宇宙射线μ子衰减的前后不对称性，为弱相互作用中的奇偶校验违规提供了教学观。探测器系统由六个垂直排成一排的塑料闪烁体组成。衰减e的向后前进不对称^-和e ⁺相对于μ子的运动方向的角度与停止在闪烁器中的μ子的入射深度相关。为了更好地解释数据并优化数据分析，进行了MC模拟。在研究的能量范围内，宇宙射线μ子的衰减推论为0.051 0.027的前后不对称性。结果与弱交互中违反奇偶性的图片一致。实验可以由高年级本科生在课程老师的指导下进行。