Improving Nuclear Safety of Fast Reactors by Slowing Down Fission Chain Reaction

Table 4

Neutron-physical characteristics of different materials.

Material	Slowing-down probability; (0.1 MeV0.5 eV)	(cm)	(cm)	Neutron lifetime (ms)
				Slowing down	Thermal
Pbnat	0.304	134	30	0.56	0.8
^208Pb	0.993	134	835	0.56	598
D2O	0.999	19	360	0.01	130
Graphite	0.998	31	138	0.03	13
Radiogenic Pb from different deposits
Brazil	0.930	134	186	0.56	29
Australia	0.914	134	142	0.56	17
The USA	0.885	134	129	0.56	14
Ukraine	0.915	134	145	0.56	18