Most of the isotope data on this site has been obtained from the National Nuclear Data Center.
Naturally Occurring Isotopes
| Mass Number | Natural Abundance | Half-life |
| 39 | 93.2581% | STABLE |
| 40 | 0.0117% | 1.248×10+9 years |
| 41 | 6.7302% | STABLE |
Known Isotopes
| Mass Number | Half-life | Decay Mode | Branching Percentage |
| 32 | No Data Available | Proton Emission (suspected) | No Data Available |
| 33 | < 25 nanoseconds | Proton Emission | No Data Available |
| 34 | < 25 nanoseconds | Proton Emission | No Data Available |
| 35 | 178 milliseconds | Electron Capture | 100.00% |
| Electron Capture with delayed Proton Emission | 0.37% | ||
| 36 | 342 milliseconds | Electron Capture | 100.00% |
| Electron Capture with delayed Proton Emission | 0.05% | ||
| Electron Capture with delayed Alpha Decay | 3.4×10-3 % | ||
| 37 | 1.226 seconds | Electron Capture | 100.00% |
| 38 | 7.636 minutes | Electron Capture | 100.00% |
| 38m | 924.3 milliseconds | Electron Capture | 99.97% |
| Isomeric Transition | 0.03% | ||
| 39 | STABLE | - | - |
| 40 | 1.248×10+9 years | Beta-minus Decay | 89.28% |
| Electron Capture | 10.72% | ||
| 41 | STABLE | - | - |
| 42 | 12.321 hours | Beta-minus Decay | 100.00% |
| 43 | 22.3 hours | Beta-minus Decay | 100.00% |
| 44 | 22.13 minutes | Beta-minus Decay | 100.00% |
| 45 | 17.81 minutes | Beta-minus Decay | 100.00% |
| 46 | 105 seconds | Beta-minus Decay | 100.00% |
| 47 | 17.50 seconds | Beta-minus Decay | 100.00% |
| 48 | 6.8 seconds | Beta-minus Decay with delayed Neutron Emission | 1.14% |
| Beta-minus Decay | 100.00% | ||
| 49 | 1.26 seconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 86.00% | ||
| 50 | 472 milliseconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 29.00% | ||
| 51 | 365 milliseconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | 47.00% | ||
| 52 | 118 milliseconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | ~ 73.00% | ||
| 53 | 30 milliseconds | Beta-minus Decay with delayed Neutron Emission | ~ 75.00% |
| Beta-minus Decay with delayed Double Neutron Emission | < 10% | ||
| Beta-minus Decay | 100.00% | ||
| 54 | 10 milliseconds | Beta-minus Decay | 100.00% |
| Beta-minus Decay with delayed Neutron Emission | > 0.00% | ||
| 55 | > 360 nanoseconds | Beta-minus Decay | No Data Available |
| Beta-minus Decay with delayed Neutron Emission | No Data Available | ||
| 56 | > 620 nanoseconds | Beta-minus Decay | No Data Available |
| 56m | 620 nanoseconds | Beta-minus Decay with delayed Neutron Emission (suspected) | No Data Available |
| 56m1 | > 620 nanoseconds | Beta-minus Decay with delayed Double Neutron Emission (suspected) | No Data Available |
This page is maintained by Steve Gagnon.