柯林斯詞典beta decay 1. N the radioactive transformation of an atomic nucleus accompanying the emission of an electron. It involves unit change of atomic number but none in mass number β衰變 (Also called beta transformation, beta process) 返回 beta decay劍橋詞典the process in which a neutron breaks up into a proton and an electron ?衰變（一種放衰變過程，原子中的不帶電的中子分裂爲一個帶一正電荷的質子和一個帶一負電荷的電子） 返回 beta decay