User:JWB/Table of fission products

Yield is usually expressed relative to number of fissioning nuclei, not the number of fission product nuclei, that is, yields should sum to 200%.

Here are yields for notable (halflife greater than one year, plus iodine-131) radioactive fission products, and (the few most absorptive) neutron poison fission products, from thermal neutron fission of U-235 (typical of nuclear power reactors), computed from [1]. These sum to only 45.5522%; the unlisted 154.4478% decay with halflife less than one year into nonradioactive nuclei.

Besides fission products, other types of radioactive products are reprocessed uranium, plutonium, minor actinides, tritium, and activation products.

⁷⁵Zn	⁷⁶Ga	⁷⁷Ge	⁷⁸As	⁷⁹Se	⁸⁰Br	⁸¹Kr	⁸²Rb	⁸³Sr	⁸⁴Y	⁸⁵Zr	⁸⁶Nb	⁸⁷Mo	⁸⁸Tc	⁸⁹Ru
⁷⁶Zn	⁷⁷Ga	⁷⁸Ge	⁷⁹As	⁸⁰Se	⁸¹Br	⁸²Kr	⁸³Rb	⁸⁴Sr	⁸⁵Y	⁸⁶Zr	⁸⁷Nb	⁸⁸Mo	⁸⁹Tc	⁹⁰Ru
⁷⁷Zn	⁷⁸Ga	⁷⁹Ge	⁸⁰As	⁸¹Se	⁸²Br	⁸³Kr	⁸⁴Rb	⁸⁵Sr	⁸⁶Y	⁸⁷Zr	⁸⁸Nb	⁸⁹Mo	⁹⁰Tc	⁹¹Ru
⁷⁸Zn	⁷⁹Ga	⁸⁰Ge	⁸¹As	⁸²Se	⁸³Br	⁸⁴Kr	⁸⁵Rb	⁸⁶Sr	⁸⁷Y	⁸⁸Zr	⁸⁹Nb	⁹⁰Mo	⁹¹Tc	⁹²Ru
⁷⁹Zn	⁸⁰Ga	⁸¹Ge	⁸²As	⁸³Se	⁸⁴Br	⁸⁵Kr	⁸⁶Rb	⁸⁷Sr	⁸⁸Y	⁸⁹Zr	⁹⁰Nb	⁹¹Mo	⁹²Tc	⁹³Ru
⁸⁰Zn	⁸¹Ga	⁸²Ge	⁸³As	⁸⁴Se	⁸⁵Br	⁸⁶Kr	⁸⁷Rb	⁸⁸Sr	⁸⁹Y	⁹⁰Zr	⁹¹Nb	⁹²Mo	⁹³Tc	⁹⁴Ru
⁸¹Zn	⁸²Ga	⁸³Ge	⁸⁴As	⁸⁵Se	⁸⁶Br	⁸⁷Kr	⁸⁸Rb	⁸⁹Sr	⁹⁰Y	⁹¹Zr	⁹²Nb	⁹³Mo	⁹⁴Tc	⁹⁵Ru
⁸²Zn	⁸³Ga	⁸⁴Ge	⁸⁵As	⁸⁶Se	⁸⁷Br	⁸⁸Kr	⁸⁹Rb	⁹⁰Sr	⁹¹Y	⁹²Zr	⁹³Nb	⁹⁴Mo	⁹⁵Tc	⁹⁶Ru
⁸³Zn	⁸⁴Ga	⁸⁵Ge	⁸⁶As	⁸⁷Se	⁸⁸Br	⁸⁹Kr	⁹⁰Rb	⁹¹Sr	⁹²Y	⁹³Zr	⁹⁴Nb	⁹⁵Mo	⁹⁶Tc	⁹⁷Ru
⁸⁴Zn	⁸⁵Ga	⁸⁶Ge	⁸⁷As	⁸⁸Se	⁸⁹Br	⁹⁰Kr	⁹¹Rb	⁹²Sr	⁹³Y	⁹⁴Zr	⁹⁵Nb	⁹⁶Mo	⁹⁷Tc	⁹⁸Ru
⁸⁵Zn	⁸⁶Ga	⁸⁷Ge	⁸⁸As	⁸⁹Se	⁹⁰Br	⁹¹Kr	⁹²Rb	⁹³Sr	⁹⁴Y	⁹⁵Zr	⁹⁶Nb	⁹⁷Mo	⁹⁸Tc	⁹⁹Ru
56	⁸⁷Ga	⁸⁸Ge	⁸⁹As	⁹⁰Se	⁹¹Br	⁹²Kr	⁹³Rb	⁹⁴Sr	⁹⁵Y	⁹⁶Zr	⁹⁷Nb	⁹⁸Mo	⁹⁹Tc	¹⁰⁰Ru
57		⁸⁹Ge	⁹⁰As	⁹¹Se	⁹²Br	⁹³Kr	⁹⁴Rb	⁹⁵Sr	⁹⁶Y	⁹⁷Zr	⁹⁸Nb	⁹⁹Mo	¹⁰⁰Tc	¹⁰¹Ru
	58	⁹⁰Ge	⁹¹As	⁹²Se	⁹³Br	⁹⁴Kr	⁹⁵Rb	⁹⁶Sr	⁹⁷Y	⁹⁸Zr	⁹⁹Nb	¹⁰⁰Mo	¹⁰¹Tc	¹⁰²Ru
		59	⁹²As	⁹³Se	⁹⁴Br	⁹⁵Kr	⁹⁶Rb	⁹⁷Sr	⁹⁸Y	⁹⁹Zr	¹⁰⁰Nb	¹⁰¹Mo	¹⁰²Tc	¹⁰³Ru
			60	⁹⁴Se	⁹⁵Br	⁹⁶Kr	⁹⁷Rb	⁹⁸Sr	⁹⁹Y	¹⁰⁰Zr	¹⁰¹Nb	¹⁰²Mo	¹⁰³Tc	¹⁰⁴Ru
			61	⁹⁵Se	⁹⁶Br	⁹⁷Kr	⁹⁸Rb	⁹⁹Sr	¹⁰⁰Y	¹⁰¹Zr	¹⁰²Nb	¹⁰³Mo	¹⁰⁴Tc	¹⁰⁵Ru
				62	⁹⁷Br	⁹⁸Kr	⁹⁹Rb	¹⁰⁰Sr	¹⁰¹Y	¹⁰²Zr	¹⁰³Nb	¹⁰⁴Mo	¹⁰⁵Tc	¹⁰⁶Ru

56	¹⁰¹Rh	¹⁰²Pd	¹⁰³Ag	¹⁰⁴Cd	¹⁰⁵In	¹⁰⁶Sn	¹⁰⁷Sb	¹⁰⁸Te	¹⁰⁹I	¹¹⁰Xe		Ba
57	¹⁰²Rh	¹⁰³Pd	¹⁰⁴Ag	¹⁰⁵Cd	¹⁰⁶In	¹⁰⁷Sn	¹⁰⁸Sb	¹⁰⁹Te	¹¹⁰I	¹¹¹Xe	¹¹²Cs		57
58	¹⁰³Rh	¹⁰⁴Pd	¹⁰⁵Ag	¹⁰⁶Cd	¹⁰⁷In	¹⁰⁸Sn	¹⁰⁹Sb	¹¹⁰Te	¹¹¹I	¹¹²Xe	¹¹³Cs	¹¹⁴Ba	La
59	¹⁰⁴Rh	¹⁰⁵Pd	¹⁰⁶Ag	¹⁰⁷Cd	¹⁰⁸In	¹⁰⁹Sn	¹¹⁰Sb	¹¹¹Te	¹¹²I	¹¹³Xe	¹¹⁴Cs	¹¹⁵Ba		58
60	¹⁰⁵Rh	¹⁰⁶Pd	¹⁰⁷Ag	¹⁰⁸Cd	¹⁰⁹In	¹¹⁰Sn	¹¹¹Sb	¹¹²Te	¹¹³I	¹¹⁴Xe	¹¹⁵Cs	¹¹⁶Ba	¹¹⁷La	Ce	59
61	¹⁰⁶Rh	¹⁰⁷Pd	¹⁰⁸Ag	¹⁰⁹Cd	¹¹⁰In	¹¹¹Sn	¹¹²Sb	¹¹³Te	¹¹⁴I	¹¹⁵Xe	¹¹⁶Cs	¹¹⁷Ba	¹¹⁸La		Pr
62	¹⁰⁷Rh	¹⁰⁸Pd	¹⁰⁹Ag	¹¹⁰Cd	¹¹¹In	¹¹²Sn	¹¹³Sb	¹¹⁴Te	¹¹⁵I	¹¹⁶Xe	¹¹⁷Cs	¹¹⁸Ba	¹¹⁹La		¹²¹Pr
63	¹⁰⁸Rh	¹⁰⁹Pd	¹¹⁰Ag	¹¹¹Cd	¹¹²In	¹¹³Sn	¹¹⁴Sb	¹¹⁵Te	¹¹⁶I	¹¹⁷Xe	¹¹⁸Cs	¹¹⁹Ba	¹²⁰La	¹²¹Ce	¹²²Pr
64	¹⁰⁹Rh	¹¹⁰Pd	¹¹¹Ag	¹¹²Cd	¹¹³In	¹¹⁴Sn	¹¹⁵Sb	¹¹⁶Te	¹¹⁷I	¹¹⁸Xe	¹¹⁹Cs	¹²⁰Ba	¹²¹La	¹²²Ce	¹²³Pr
65	¹¹⁰Rh	¹¹¹Pd	¹¹²Ag	¹¹³Cd	¹¹⁴In	¹¹⁵Sn	¹¹⁶Sb	¹¹⁷Te	¹¹⁸I	¹¹⁹Xe	¹²⁰Cs	¹²¹Ba	¹²²La	¹²³Ce	¹²⁴Pr
66	¹¹¹Rh	¹¹²Pd	¹¹³Ag	¹¹⁴Cd	¹¹⁵In	¹¹⁶Sn	¹¹⁷Sb	¹¹⁸Te	¹¹⁹I	¹²⁰Xe	¹²¹Cs	¹²²Ba	¹²³La	¹²⁴Ce	¹²⁵Pr
67	¹¹²Rh	¹¹³Pd	¹¹⁴Ag	¹¹⁵Cd	¹¹⁶In	¹¹⁷Sn	¹¹⁸Sb	¹¹⁹Te	¹²⁰I	¹²¹Xe	¹²²Cs	¹²³Ba	¹²⁴La	¹²⁵Ce	¹²⁶Pr
	¹¹³Rh	¹¹⁴Pd	¹¹⁵Ag	¹¹⁶Cd	¹¹⁷In	¹¹⁸Sn	¹¹⁹Sb	¹²⁰Te	¹²¹I	¹²²Xe	¹²³Cs	¹²⁴Ba	¹²⁵La	¹²⁶Ce	¹²⁷Pr
	¹¹⁴Rh	¹¹⁵Pd	¹¹⁶Ag	¹¹⁷Cd	¹¹⁸In	¹¹⁹Sn	¹²⁰Sb	¹²¹Te	¹²²I	¹²³Xe	¹²⁴Cs	¹²⁵Ba	¹²⁶La	¹²⁷Ce	¹²⁸Pr
	¹¹⁵Rh	¹¹⁶Pd	¹¹⁷Ag	¹¹⁸Cd	¹¹⁹In	¹²⁰Sn	¹²¹Sb	¹²²Te	¹²³I	¹²⁴Xe	¹²⁵Cs	¹²⁶Ba	¹²⁷La	¹²⁸Ce	¹²⁹Pr
	¹¹⁶Rh	¹¹⁷Pd	¹¹⁸Ag	¹¹⁹Cd	¹²⁰In	¹²¹Sn	¹²²Sb	¹²³Te	¹²⁴I	¹²⁵Xe	¹²⁶Cs	¹²⁷Ba	¹²⁸La	¹²⁹Ce	¹³⁰Pr
	¹¹⁷Rh	¹¹⁸Pd	¹¹⁹Ag	¹²⁰Cd	¹²¹In	¹²²Sn	¹²³Sb	¹²⁴Te	¹²⁵I	¹²⁶Xe	¹²⁷Cs	¹²⁸Ba	¹²⁹La	¹³⁰Ce	¹³¹Pr
	¹¹⁸Rh	¹¹⁹Pd	¹²⁰Ag	¹²¹Cd	¹²²In	¹²³Sn	¹²⁴Sb	¹²⁵Te	¹²⁶I	¹²⁷Xe	¹²⁸Cs	¹²⁹Ba	¹³⁰La	¹³¹Ce	¹³²Pr
	¹¹⁹Rh	¹²⁰Pd	¹²¹Ag	¹²²Cd	¹²³In	¹²⁴Sn	¹²⁵Sb	¹²⁶Te	¹²⁷I	¹²⁸Xe	¹²⁹Cs	¹³⁰Ba	¹³¹La	¹³²Ce	¹³³Pr
	¹²⁰Rh	¹²¹Pd	¹²²Ag	¹²³Cd	¹²⁴In	¹²⁵Sn	¹²⁶Sb	¹²⁷Te	¹²⁸I	¹²⁹Xe	¹³⁰Cs	¹³¹Ba	¹³²La	¹³³Ce	¹³⁴Pr
	¹²¹Rh	¹²²Pd	¹²³Ag	¹²⁴Cd	¹²⁵In	¹²⁶Sn	¹²⁷Sb	¹²⁸Te	¹²⁹I	¹³⁰Xe	¹³¹Cs	¹³²Ba	¹³³La	¹³⁴Ce	¹³⁵Pr
	¹²²Rh	¹²³Pd	¹²⁴Ag	¹²⁵Cd	¹²⁶In	¹²⁷Sn	¹²⁸Sb	¹²⁹Te	¹³⁰I	¹³¹Xe	¹³²Cs	¹³³Ba	¹³⁴La	¹³⁵Ce	¹³⁶Pr
	¹²³Rh	¹²⁴Pd	¹²⁵Ag	¹²⁶Cd	¹²⁷In	¹²⁸Sn	¹²⁹Sb	¹³⁰Te	¹³¹I	¹³²Xe	¹³³Cs	¹³⁴Ba	¹³⁵La	¹³⁶Ce	¹³⁷Pr
	¹²⁴Rh	¹²⁵Pd	¹²⁶Ag	¹²⁷Cd	¹²⁸In	¹²⁹Sn	¹³⁰Sb	¹³¹Te	¹³²I	¹³³Xe	¹³⁴Cs	¹³⁵Ba	¹³⁶La	¹³⁷Ce	¹³⁸Pr
	¹²⁵Rh	¹²⁶Pd	¹²⁷Ag	¹²⁸Cd	¹²⁹In	¹³⁰Sn	¹³¹Sb	¹³²Te	¹³³I	¹³⁴Xe	¹³⁵Cs	¹³⁶Ba	¹³⁷La	¹³⁸Ce	¹³⁹Pr
	¹²⁶Rh	¹²⁷Pd	¹²⁸Ag	¹²⁹Cd	¹³⁰In	¹³¹Sn	¹³²Sb	¹³³Te	¹³⁴I	¹³⁵Xe	¹³⁶Cs	¹³⁷Ba	¹³⁸La	¹³⁹Ce	¹⁴⁰Pr
	¹²⁷Rh	¹²⁸Pd	¹²⁹Ag	¹³⁰Cd	¹³¹In	¹³²Sn	¹³³Sb	¹³⁴Te	¹³⁵I	¹³⁶Xe	¹³⁷Cs	¹³⁸Ba	¹³⁹La	¹⁴⁰Ce	¹⁴¹Pr
	¹²⁸Rh	¹²⁹Pd	¹³⁰Ag	¹³¹Cd	¹³²In	¹³³Sn	¹³⁴Sb	¹³⁵Te	¹³⁶I	¹³⁷Xe	¹³⁸Cs	¹³⁹Ba	¹⁴⁰La	¹⁴¹Ce	¹⁴²Pr
	84	¹³⁰Pd	¹³¹Ag	¹³²Cd	¹³³In	¹³⁴Sn	¹³⁵Sb	¹³⁶Te	¹³⁷I	¹³⁸Xe	¹³⁹Cs	¹⁴⁰Ba	¹⁴¹La	¹⁴²Ce	¹⁴³Pr
	85	¹³¹Pd	¹³²Ag	¹³³Cd	¹³⁴In	¹³⁵Sn	¹³⁶Sb	¹³⁷Te	¹³⁸I	¹³⁹Xe	¹⁴⁰Cs	¹⁴¹Ba	¹⁴²La	¹⁴³Ce	¹⁴⁴Pr
		86		¹³⁴Cd	¹³⁵In	¹³⁶Sn	¹³⁷Sb	¹³⁸Te	¹³⁹I	¹⁴⁰Xe	¹⁴¹Cs	¹⁴²Ba	¹⁴³La	¹⁴⁴Ce	¹⁴⁵Pr
			87		¹³⁶In	¹³⁷Sn	¹³⁸Sb	¹³⁹Te	¹⁴⁰I	¹⁴¹Xe	¹⁴²Cs	¹⁴³Ba	¹⁴⁴La	¹⁴⁵Ce	¹⁴⁶Pr

82	¹⁴²Nd	¹⁴³Pm	¹⁴⁴Sm	¹⁴⁵Eu	¹⁴⁶Gd	¹⁴⁷Tb	¹⁴⁸Dy	¹⁴⁹Ho	¹⁵⁰Er	¹⁵¹Tm	¹⁵²Yb	¹⁵³Lu	¹⁵⁴Hf	¹⁵⁵Ta	¹⁵⁶W
83	¹⁴³Nd	¹⁴⁴Pm	¹⁴⁵Sm	¹⁴⁶Eu	¹⁴⁷Gd	¹⁴⁸Tb	¹⁴⁹Dy	¹⁵⁰Ho	¹⁵¹Er	¹⁵²Tm	¹⁵³Yb	¹⁵⁴Lu	¹⁵⁵Hf	¹⁵⁶Ta	¹⁵⁷W
84	¹⁴⁴Nd	¹⁴⁵Pm	¹⁴⁶Sm	¹⁴⁷Eu	¹⁴⁸Gd	¹⁴⁹Tb	¹⁵⁰Dy	¹⁵¹Ho	¹⁵²Er	¹⁵³Tm	¹⁵⁴Yb	¹⁵⁵Lu	¹⁵⁶Hf	¹⁵⁷Ta	¹⁵⁸W
85	¹⁴⁵Nd	¹⁴⁶Pm	¹⁴⁷Sm	¹⁴⁸Eu	¹⁴⁹Gd	¹⁵⁰Tb	¹⁵¹Dy	¹⁵²Ho	¹⁵³Er	¹⁵⁴Tm	¹⁵⁵Yb	¹⁵⁶Lu	¹⁵⁷Hf	¹⁵⁸Ta	¹⁵⁹W
86	¹⁴⁶Nd	¹⁴⁷Pm	¹⁴⁸Sm	¹⁴⁹Eu	¹⁵⁰Gd	¹⁵¹Tb	¹⁵²Dy	¹⁵³Ho	¹⁵⁴Er	¹⁵⁵Tm	¹⁵⁶Yb	¹⁵⁷Lu	¹⁵⁸Hf	¹⁵⁹Ta	¹⁶⁰W
87	¹⁴⁷Nd	¹⁴⁸Pm	¹⁴⁹Sm	¹⁵⁰Eu	¹⁵¹Gd	¹⁵²Tb	¹⁵³Dy	¹⁵⁴Ho	¹⁵⁵Er	¹⁵⁶Tm	¹⁵⁷Yb	¹⁵⁸Lu	¹⁵⁹Hf	¹⁶⁰Ta	¹⁶¹W
88	¹⁴⁸Nd	¹⁴⁹Pm	¹⁵⁰Sm	¹⁵¹Eu	¹⁵²Gd	¹⁵³Tb	¹⁵⁴Dy	¹⁵⁵Ho	¹⁵⁶Er	¹⁵⁷Tm	¹⁵⁸Yb	¹⁵⁹Lu	¹⁶⁰Hf	¹⁶¹Ta	¹⁶²W
89	¹⁴⁹Nd	¹⁵⁰Pm	¹⁵¹Sm	¹⁵²Eu	¹⁵³Gd	¹⁵⁴Tb	¹⁵⁵Dy	¹⁵⁶Ho	¹⁵⁷Er	¹⁵⁸Tm	¹⁵⁹Yb	¹⁶⁰Lu	¹⁶¹Hf	¹⁶²Ta	¹⁶³W
90	¹⁵⁰Nd	¹⁵¹Pm	¹⁵²Sm	¹⁵³Eu	¹⁵⁴Gd	¹⁵⁵Tb	¹⁵⁶Dy	¹⁵⁷Ho	¹⁵⁸Er	¹⁵⁹Tm	¹⁶⁰Yb	¹⁶¹Lu	¹⁶²Hf	¹⁶³Ta	¹⁶⁴W
91	¹⁵¹Nd	¹⁵²Pm	¹⁵³Sm	¹⁵⁴Eu	¹⁵⁵Gd	¹⁵⁶Tb	¹⁵⁷Dy	¹⁵⁸Ho	¹⁵⁹Er	¹⁶⁰Tm	¹⁶¹Yb	¹⁶²Lu	¹⁶³Hf	¹⁶⁴Ta	¹⁶⁵W
92	¹⁵²Nd	¹⁵³Pm	¹⁵⁴Sm	¹⁵⁵Eu	¹⁵⁶Gd	¹⁵⁷Tb	¹⁵⁸Dy	¹⁵⁹Ho	¹⁶⁰Er	¹⁶¹Tm	¹⁶²Yb	¹⁶³Lu	¹⁶⁴Hf	¹⁶⁵Ta	¹⁶⁶W
93	¹⁵³Nd	¹⁵⁴Pm	¹⁵⁵Sm	¹⁵⁶Eu	¹⁵⁷Gd	¹⁵⁸Tb	¹⁵⁹Dy	¹⁶⁰Ho	¹⁶¹Er	¹⁶²Tm	¹⁶³Yb	¹⁶⁴Lu	¹⁶⁵Hf	¹⁶⁶Ta	¹⁶⁷W
94	¹⁵⁴Nd	¹⁵⁵Pm	¹⁵⁶Sm	¹⁵⁷Eu	¹⁵⁸Gd	¹⁵⁹Tb	¹⁶⁰Dy	¹⁶¹Ho	¹⁶²Er	¹⁶³Tm	¹⁶⁴Yb	¹⁶⁵Lu	¹⁶⁶Hf	¹⁶⁷Ta	¹⁶⁸W
	¹⁵⁵Nd	¹⁵⁶Pm	¹⁵⁷Sm	¹⁵⁸Eu	¹⁵⁹Gd	¹⁶⁰Tb	¹⁶¹Dy	¹⁶²Ho	¹⁶³Er	¹⁶⁴Tm	¹⁶⁵Yb	¹⁶⁶Lu	¹⁶⁷Hf	¹⁶⁸Ta	¹⁶⁹W
	¹⁵⁶Nd	¹⁵⁷Pm	¹⁵⁸Sm	¹⁵⁹Eu	¹⁶⁰Gd	¹⁶¹Tb	¹⁶²Dy	¹⁶³Ho	¹⁶⁴Er	¹⁶⁵Tm	¹⁶⁶Yb	¹⁶⁷Lu	¹⁶⁸Hf	¹⁶⁹Ta	¹⁷⁰W
	¹⁵⁷Nd	¹⁵⁸Pm	¹⁵⁹Sm	¹⁶⁰Eu	¹⁶¹Gd	¹⁶²Tb	¹⁶³Dy	¹⁶⁴Ho	¹⁶⁵Er	¹⁶⁶Tm	¹⁶⁷Yb	¹⁶⁸Lu	¹⁶⁹Hf	¹⁷⁰Ta	¹⁷¹W
	¹⁵⁸Nd	¹⁵⁹Pm	¹⁶⁰Sm	¹⁶¹Eu	¹⁶²Gd	¹⁶³Tb	¹⁶⁴Dy	¹⁶⁵Ho	¹⁶⁶Er	¹⁶⁷Tm	¹⁶⁸Yb	¹⁶⁹Lu	¹⁷⁰Hf	¹⁷¹Ta	¹⁷²W

Ordered by yield (thermal neutron fission of U-235)

Yield	Isotope	Halflife	Comment
6.7896%	¹³³Cs → ¹³⁴Cs	2.065y	neutron capture (29 barns) slowly converts stable ¹³³Cs to ¹³⁴Cs, which itself is low-yield because beta decay stops at ¹³⁴Xe; can be further converted (140 barns) to ¹³⁵Cs
6.3333%	¹³⁵I → ¹³⁵Xe	6.57h	most important neutron poison; neutron capture converts 10%-50% of ¹³⁵Xe to ¹³⁶Xe; remainder decays (9.14h) to ¹³⁵Cs (2.3my)
6.2956%	⁹³Zr	1.53my
6.0899%	¹³⁷Cs	30.17y
6.0507%	⁹⁹Tc	211ky	Candidate for disposal by nuclear transmutation
5.7518%	⁹⁰Sr	28.9y
2.8336%	¹³¹I	8.02d
2.2713%	¹⁴⁷Pm	2.62y
1.0888%	¹⁴⁹Sm	nonradioactive	2nd most significant neutron poison
0.6576%	¹²⁹I	15.7my	Candidate for disposal by nuclear transmutation
0.4203%	¹⁵¹Sm	90y	neutron poison; most will be converted to stable ¹⁵²Sm
0.3912%	¹⁰⁶Ru	373.6d
0.2717%	⁸⁵Kr	10.78y
0.1629%	¹⁰⁷Pd	6.5my
0.0508%	⁷⁹Se	295ky
0.0330%	¹⁵⁵Eu → ¹⁵⁵Gd	4.76y	both neutron poisons
0.0297%	¹²⁵Sb	2.76y
0.0236%	¹²⁶Sn	230ky
0.0065%	¹⁵⁷Gd	nonradioactive	neutron poison
0.0003%	^113mCd	14.1y

Ordered by mass number

Yield	Isotope
0.0508%	selenium-79
0.2717%	krypton-85
5.7518%	strontium-90
6.2956%	zirconium-93
6.0507%	technetium-99
0.3912%	ruthenium-106
0.1629%	palladium-107
0.0003%	cadmium-113m
0.0297%	antimony-125
0.0236%	tin-126
0.6576%	iodine-129
2.8336%	iodine-131
6.7896%	cesium-133	→	cesium-134
6.3333%	iodine-135	→	xenon-135	→	cesium-135
6.0899%	cesium-137
2.2713%	promethium-147
1.0888%	samarium-149
0.4203%	samarium-151
0.0330%	europium-155	→	gadolinium-155
0.0065%	gadolinium-157

Ordered by halflife

Yield	Isotope	Halflife	Comment
2.8336%	¹³¹I	8.02d	Important in nuclear explosions and accidents but not in cooled spent nuclear fuel
0.3912%	¹⁰⁶Ru	373.6d
6.7896%	¹³³Cs → ¹³⁴Cs	2.065y	neutron capture slowly converts stable ¹³³Cs to ¹³⁴Cs, which itself is low-yield because beta decay stops at ¹³⁴Xe
2.2713%	¹⁴⁷Pm	2.62y
0.0297%	¹²⁵Sb	2.76y
<0.0330%	¹⁵⁵Eu → ¹⁵⁵Gd	4.76y	both neutron poisons
0.2717%	⁸⁵Kr	10.78y	Usually dispersed in atmosphere on nuclear reprocessing
<0.0003%	^113mCd	14.1y
5.7518%	⁹⁰Sr	28.9y
6.0899%	¹³⁷Cs	30.17y
<0.4203%	¹⁵¹Sm	90y	Most will be destroyed by neutron capture while still in reactor
6.0507%	⁹⁹Tc	211ky	Candidate for disposal by nuclear transmutation
0.0236%	¹²⁶Sn	230ky
0.0508%	⁷⁹Se	295ky
6.2956%	⁹³Zr	1.53my
<6.3333%	¹³⁵Cs	2.3my
0.1629%	¹⁰⁷Pd	6.5my
0.6576%	¹²⁹I	15.7my	Candidate for disposal by nuclear transmutation
<1.0888%	¹⁴⁹Sm	nonradioactive	neutron poison
<0.0065%	¹⁵⁷Gd	nonradioactive	neutron poison

Ordered by thermal neutron neutron absorption cross section

Barns	Yield	Isotope	Halflife	Comment
2650000	6.3333%	¹³⁵I → ¹³⁵Xe	6.57d	Most important neutron poison; neutron capture rapidly converts ¹³⁵Xe to ¹³⁶Xe; remainder decays (9.14h) to ¹³⁵Cs (2.3my)
254000	0.0065%	¹⁵⁷Gd	nonradioactive	neutron poison, but low yield
40140	1.0888%	¹⁴⁹Sm	nonradioactive	2nd most important neutron poison
20600	0.0003%	^113mCd	14.1y
15200	0.4203%	¹⁵¹Sm	90y	most will be destroyed by neutron capture
3950	0.0330%	¹⁵⁵Eu → ¹⁵⁵Gd	4.76y	both neutron poisons
96	2.2713%	¹⁴⁷Pm	2.62y
80	2.8336%	¹³¹I	8.02d
29	6.7896%	¹³³Cs → ¹³⁴Cs	2.065y	neutron capture slowly converts stable ¹³³Cs to ¹³⁴Cs, which itself is low-yield because beta decay stops at ¹³⁴Xe
20	6.0507%	⁹⁹Tc	211ky
18	0.6576%	¹²⁹I	15.7my
2.7	6.2956%	⁹³Zr	1.53my
1.8	0.1629%	¹⁰⁷Pd	6.5my
1.66	0.2717%	⁸⁵Kr	10.78y
0.90	5.7518%	⁹⁰Sr	28.9y
0.15	0.3912%	¹⁰⁶Ru	373.6d
0.11	6.0899%	¹³⁷Cs	30.17y
	0.0297%	¹²⁵Sb	2.76y
	0.0236%	¹²⁶Sn	230ky
	0.0508%	⁷⁹Se	295ky