Taw qhia rau cov khoom siv xov tooj cua
Cov khoom siv hluav taws xob (kom paub meej, radionuclides) yog cov khoom sib txawv lossis cov duab hluav taws xob (xws li alpha rays, beta rays, gamma rays, thiab lwm yam) uas tuaj yeem tawm ntawm cov tsis muaj zog atomic nucleus, tso lub zog rau tib lub sijhawm, thiab nws thiaj li ua kom lwj. ruaj khov Cov ntsiab lus Thiab nres emitting ntsiab. Cov cuab yeej no hu ua radioactivity, thiab cov txheej txheem no hu ua hluav taws xob tsis zoo. Cov ntxhia uas muaj cov khoom ua pa (xws li U, Th, Ra, thiab lwm yam) hu ua cov pa tshuaj lom neeg.