Alpha nuclide
An alpha nuclide is a nuclide that consists of an integer number of alpha particles. Alpha nuclides have equal, even numbers of protons and neutrons; they are important in stellar nucleosynthesis since the energetic environment within stars is amenable to fusion of alpha particles into heavier nuclei.[1][2] Stable alpha nuclides, and stable decay products of radioactive alpha nuclides, are some of the most common metals in the universe.
Alpha nuclide is also shorthand for alpha radionuclide, referring to those radioactive isotopes that undergo alpha decay and thereby emit alpha particles.[3]
List of alpha nuclides
Alpha number | nuclide | Stable/radioactive | decay mode | half-life[4] | product(s) of decay (bold is stable) | notes |
---|---|---|---|---|---|---|
1 | 4 2He |
Stable | ||||
2 | 8 4Be |
Radioactive | α | 8.19(37)×10−17 s | 4 2He |
|
3 | 12 6C |
Stable | ||||
4 | 16 8O |
Stable | ||||
5 | 20 10Ne |
Stable | ||||
6 | 24 12Mg |
Stable | ||||
7 | 28 14Si |
Stable | ||||
8 | 32 16S |
Stable | ||||
9 | 36 18Ar |
Observationally Stable | ||||
10 | 40 20Ca |
Observationally Stable | ||||
11 | 44 22Ti |
Radioactive | EC | 60.0(11) y | 44 21Sc → 44 20Ca |
|
12 | 48 24Cr |
Radioactive | β+ | 21.56(3) h | 48 23V → 48 22Ti |
|
13 | 52 26Fe |
Radioactive | β+ | 8.275(8) h | 52 25Mn → 52 24Cr |
|
14 | 56 28Ni |
Radioactive | β+ | 6.075(10) d | 56 27Co → 56 26Fe |
|
15 | 60 30Zn |
Radioactive | β+ | 2.38(5) min | 60 29Cu → 60 28Ni |
The nuclear binding energy of alpha nuclides heavier than zinc-60 (beginning with germanium-64) is too large for them be formed by fusion processes. As of 2018, the heaviest known alpha nuclide is xenon-108.[5]
References
- Appenzeller; Harwit; Kippenhahn; Strittmatter; Trimble, eds. (1998). Astrophysics Library (3rd ed.). New York: Springer.
- Carroll, Bradley W. & Ostlie, Dale A. (2007). An Introduction to Modern Stellar Astrophysics. Addison Wesley, San Francisco. ISBN 978-0-8053-0348-3.
- John Avison (November 2014). The World of Physics. Nelson Thornes. pp. 397–. ISBN 978-0-17-438733-6.
- Audi, G.; Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S. (2017). "The NUBASE2016 evaluation of nuclear properties" (PDF). Chinese Physics C. 41 (3): 030001. Bibcode:2017ChPhC..41c0001A. doi:10.1088/1674-1137/41/3/030001.
- Auranen, K.; et al. (2018). "Superallowed α decay to doubly magic 100Sn" (PDF). Physical Review Letters. 121 (18): 182501. doi:10.1103/PhysRevLett.121.182501. PMID 30444390.