radioactivity
Radioactivity yog hais txog kev sib kis ntawm hluav taws xob los ntawm cov hluav taws xob tsis ruaj khov (xws li α duab hluav taws xob, hluav taws xob, hluav taws xob, thiab lwm yam) thiab txiav tawm los ua cov khoom ruaj khov thiab nres hluav taws xob (cov khoom lwj). Qhov tshwm sim no yog hu ua radioactivity.