Pu
Plutonium
Z = 94 · Actinide · 244.0 u
Nuclear Engineering Significance
Pu-239 is the most important man-made fissile isotope, bred from U-238 neutron capture. It contributes ~40% of fissions in a standard LWR fuel cycle by end of life. MOX fuel (mixed PuO₂-UO₂) recycles plutonium. Higher isotopes (Pu-240, Pu-241, Pu-242) build up with burnup and significantly affect reactivity and kinetics parameters.
Basic properties
- Atomic number (Z)
- 94
- Standard atomic mass
- 244.0 u
- Category
- Actinide
Isotopes & cross-section data
| Isotope | Mass (A) | Half-life | ZAID | Libraries |
|---|---|---|---|---|
| Pu-238 | 238 | 87.7 y | .80c.71c.70c | |
| Pu-239 | 239 | 2.411e4 y | .80c.71c.70c | |
| Pu-240 | 240 | 6561 y | .80c.71c.70c | |
| Pu-241 | 241 | 14.29 y | .80c.71c.70c | |
| Pu-242 | 242 | 3.75e5 y | .80c.71c.70c | |
| Pu-244 | 244 | 8.0e7 y | .80c |