It's Elemental
Isotopes of the Element Promethium
Promethium
Most of the isotope data on this site has been obtained from the National Nuclear Data Center. Please visit their site for more information.
Known Isotopes
| Mass Number | Half-life | Decay Mode | Branching Percentage |
| 126 | No Data Available | Electron Capture (suspected) | No Data Available |
| 127 | No Data Available | Proton Emission (suspected) | No Data Available |
| Electron Capture (suspected) | No Data Available | ||
| 128 | 1.0 seconds | Electron Capture | 100.00% |
| Alpha Decay | No Data Available | ||
| Electron Capture with delayed Proton Emission | No Data Available | ||
| 129 | 2.4 seconds | Electron Capture | 100.00% |
| 130 | 2.6 seconds | Electron Capture | 100.00% |
| Electron Capture with delayed Proton Emission | No Data Available | ||
| 131 | 6.3 seconds | Electron Capture | 100.00% |
| 132 | 6.2 seconds | Electron Capture | 100.00% |
| Electron Capture with delayed Proton Emission | ~ 5.0×10-5 % | ||
| 133 | 13.5 seconds | Electron Capture | 100.00% |
| 133m | < 8.8 seconds | Isomeric Transition | No Data Available |
| Electron Capture | No Data Available | ||
| 134 | ≈ 5 seconds | Electron Capture | 100.00% |
| 134m | 22 seconds | Electron Capture | 100.00% |
| 135 | 49 seconds | Electron Capture | 100.00% |
| 135m | 45 seconds | Electron Capture | 100.00% |
| 136 | 107 seconds | Electron Capture | 100.00% |
| 136m | 47 seconds | Electron Capture | 100.00% |
| 137 | 2.4 minutes | Electron Capture | 100.00% |
| 138 | 10 seconds | Electron Capture | 100.00% |
| 138m | 3.24 minutes | Electron Capture | No Data Available |
| 139 | 4.15 minutes | Electron Capture | 100.00% |
| 139m | 180 milliseconds | Isomeric Transition | 99.94% |
| Electron Capture | 0.06% | ||
| 140 | 9.2 seconds | Electron Capture | 100.00% |
| 140m | 5.95 minutes | Electron Capture | 100.00% |
| 141 | 20.90 minutes | Electron Capture | 100.00% |
| 142 | 40.5 seconds | Electron Capture | 100.00% |
| 142m | 2.0 milliseconds | Isomeric Transition | 100.00% |
| 143 | 265 days | Electron Capture | 100.00% |
| 144 | 363 days | Electron Capture | 100.00% |
| 145 | 17.7 years | Electron Capture | 100.00% |
| Alpha Decay | 2.8×10-7 % | ||
| 146 | 5.53 years | Electron Capture | 66.00% |
| Beta-minus Decay | 34.00% | ||
| 147 | 2.6234 years | Beta-minus Decay | 100.00% |
| 148 | 5.368 days | Beta-minus Decay | 100.00% |
| 148m | 41.29 days | Beta-minus Decay | 95.80% |
| Isomeric Transition | 4.20% | ||
| 149 | 53.08 hours | Beta-minus Decay | 100.00% |
| 150 | 2.68 hours | Beta-minus Decay | 100.00% |
| 151 | 28.40 hours | Beta-minus Decay | 100.00% |
| 152 | 4.12 minutes | Beta-minus Decay | 100.00% |
| 152m | 13.8 minutes | Beta-minus Decay | 100.00% |
| Isomeric Transition | >= 0.00% | ||
| 152m1 | 7.52 minutes | Beta-minus Decay | 100.00% |
| 153 | 5.25 minutes | Beta-minus Decay | 100.00% |
| 154 | 2.68 minutes | Beta-minus Decay | 100.00% |
| 154m | 1.73 minutes | Beta-minus Decay | 100.00% |
| 155 | 41.5 seconds | Beta-minus Decay | 100.00% |
| 156 | 26.70 seconds | Beta-minus Decay | 100.00% |
| 157 | 10.56 seconds | Beta-minus Decay | 100.00% |
| 158 | 4.8 seconds | Beta-minus Decay | 100.00% |
| 159 | 1.5 seconds | Beta-minus Decay | 100.00% |
| 160 | No Data Available | Beta-minus Decay (suspected) | No Data Available |
| 161 | No Data Available | Beta-minus Decay (suspected) | No Data Available |
| 162 | No Data Available | Beta-minus Decay (suspected) | No Data Available |
| 163 | No Data Available | Beta-minus Decay (suspected) | No Data Available |
Citation and linking information
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