Cosmogenic radionuclide
Cosmogenic radionuclides are continuously created in the upper atmospheric layer by cosmic radiation. They occur in trace amounts on earth. The name is derived from the Greek words kosmos (κόσμος) and genesis (γένεσις), meaning "world" and "birth".The following Table shows some examples of cosmogenic radionuclides.
| nuclide | T½ (year) | abundance |
|---|---|---|
| 3H | 12.3 | traces |
| 10Be | 1.387×106 | traces |
| 14C | 5.73×103 | traces |
| 22Na | 2.6 | traces |
| 26Al | 7.17×105 | traces |
| 32Si | 153 | traces |
| 36Cl | 3.01×105 | traces |
| 39Ar | 269 | traces |
| 41Ca | 1.02×105 | traces |
| 81Kr | 2.29×105 | traces |
| 129I | 1.57×107 | traces |