[Click for Main Data] Proton Emission Neutron Emission Electron Emission Positron Emission
Most of the isotope data on this site has been obtained from the National Nuclear Data Center.
Naturally Occurring Isotopes
Californium has no naturally occurring isotopes.
Known Isotopes
| Mass Number | Half-life | Decay Mode | Branching Percentage |
| 237 | 0.8 seconds | Spontaneous Fission | 70.00% |
| Alpha Decay | 30.00% | ||
| 238 | 21 milliseconds | Spontaneous Fission | 100.00% |
| 239 | 39 seconds | Electron Capture | No Data Available |
| Alpha Decay | No Data Available | ||
| 240 | 64 seconds | Alpha Decay | 98.50% |
| Spontaneous Fission | 1.50% | ||
| 241 | 3.78 minutes | Electron Capture | ~ 75.00% |
| Alpha Decay | ~ 25.00% | ||
| 242 | 3.7 minutes | Alpha Decay | 80.00% |
| Electron Capture | 20.00% | ||
| Spontaneous Fission | <= 0.01% | ||
| 243 | 10.7 minutes | Alpha Decay | ~ 14.00% |
| Electron Capture | ~ 86.00% | ||
| 244 | 19.4 minutes | Alpha Decay | <= 100.00% |
| 245 | 45.0 minutes | Electron Capture | 64.70% |
| Alpha Decay | 35.30% | ||
| 246 | 35.7 hours | Alpha Decay | 100.00% |
| Electron Capture | < 4.0×10-3 % | ||
| Spontaneous Fission | 2.4×10-4 % | ||
| 246m | 45 nanoseconds | Spontaneous Fission | <= 100.00% |
| 247 | 3.11 hours | Electron Capture | 99.97% |
| Alpha Decay | 0.04% | ||
| 248 | 333.5 days | Alpha Decay | 100.00% |
| Spontaneous Fission | 2.9×10-3 % | ||
| 249 | 351 years | Alpha Decay | 100.00% |
| Spontaneous Fission | 5.0×10-7 % | ||
| 250 | 13.08 years | Alpha Decay | 99.92% |
| Spontaneous Fission | 0.08% | ||
| 251 | 898 years | Alpha Decay | 100.00% |
| Spontaneous Fission | No Data Available | ||
| 252 | 2.645 years | Alpha Decay | 96.91% |
| Spontaneous Fission | 3.09% | ||
| 253 | 17.81 days | Alpha Decay | 0.31% |
| Beta-minus Decay | 99.69% | ||
| 254 | 60.5 days | Spontaneous Fission | 99.69% |
| Alpha Decay | 0.31% | ||
| 255 | 85 minutes | Beta-minus Decay | 100.00% |
| 256 | 12.3 minutes | Spontaneous Fission | 100.00% |
| Beta-minus Decay | < 1.00% | ||
| Alpha Decay | ~ 1.0×10-6 % |
This page is maintained by Steve Gagnon.