Plutonium-239
The first sample of plutonium in which nuclear fission was detected, pictured above, was a sample of plutonium-239. | |
| General | |
|---|---|
| Symbol | 239Pu |
| Names | plutonium-239 |
| Protons (Z) | 94 |
| Neutrons (N) | 145 |
| Nuclide data | |
| Half-life (t1/2) | 24110 years |
| Isotope mass | 239.0521634 Da |
| Spin | +1⁄2 |
| Parent isotopes | 243Cm (α) 239Am (EC) 239Np (β−) |
| Decay products | 235U |
| Decay modes | |
| Decay mode | Decay energy (MeV) |
| Alpha decay | 5.156 |
| Isotopes of plutonium Complete table of nuclides | |
Plutonium-239 (239
Pu or Pu-239) is an isotope of plutonium. Plutonium-239 is the primary fissile isotope used for the production of nuclear weapons, although uranium-235 is also used for that purpose. Plutonium-239 is also one of the three main isotopes demonstrated usable as fuel in thermal spectrum nuclear reactors, along with uranium-235 and uranium-233. Plutonium-239 has a half-life of 24,110 years.