A discovery that neutrinos, virtually massless particles, convert into other forms known as muon and tau before they lea发现中微子（几乎是无质量的粒子）在离开太阳之前可转化介子，解开了一个40年的谜。
The theory is that when a muon encounters a gas molecule, it can knock off an electron, leaving a positively charged ion有理论认为：当一个μ子遇到一个气体分子时，它会电离出一个电子，剩下的部分则形成一个正离子。