夸克不仅带有重子数、电荷，而且也带有轻子荷。
The quarks have not only baryon number and charge but also lepton charge.
介子轻子族中的一种基本微粒(非介子)，其质量为电子的209倍，是一种负电荷，平均寿命为2。
An elementary particle in the lepton family (not a meson), having a mass209 times that of the electron, a negative electric charge, and a mean lifetime of2.2? 0-6 second.
应用推荐