Duba wurin da ke ƙasa sannan ka amsa tambayar daga baya a cikin harshe ɗaya kamar yadda wurin yake:  Passage: Yawancin masu amfani da fission sune masu amfani da wutar lantarki na thermal-neutron waɗanda ke amfani da mai kula da neutron don rage gudu ("thermalize") neutrons da aka samar ta hanyar fission na nukiliya. Matsakaici yana ƙaruwa da ƙwanƙwasa ƙwanƙwasawa don ƙwayoyin fissile kamar uranium-235 ko plutonium-239. Bugu da ƙari, uranium-238 yana da ƙananan ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin ƙarancin. Haɗin waɗannan tasirin yana ba da damar yin amfani da injin ruwa mai sauƙi don amfani da uranium mai ƙarancin ƙarfi. Rukunin ruwa mai nauyi da masu sarrafa graphite na iya amfani da uranium na halitta kamar yadda waɗannan masu daidaitawa ke da ƙananan ƙananan ƙarancin ƙarancin neutron fiye da ruwa mai sauƙi. Ƙara yawan zafin jiki na man fetur kuma yana ƙaruwa da ɗaukar neutron thermal na U-238 ta hanyar fadada Doppler, yana ba da mummunan ra'ayi don taimakawa wajen sarrafa injin. Hakanan, lokacin da mai daidaitawa shima mai sanyaya ne (ruwa mai sauƙi ko ruwa mai nauyi), tafasa mai sanyaya zai rage yawan mai daidaitawa kuma ya samar da mummunan ra'ayi (ƙimar ɓarna mara kyau).  Tambaya: Mene ne ma'anar thermalize?
thermal-neutron reactors da suke amfani da neutron moderator don rage gudu