Alpha nuclide

{{Short description|Nuclide made up of alpha particles}}

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.{{cite book |editor=Appenzeller |editor2=Harwit |editor3=Kippenhahn |editor4= Strittmatter |editor5=Trimble |title=Astrophysics Library |publisher=Springer |location=New York |date=1998 |edition=3rd }}{{cite book |last=Carroll |first=Bradley W. |last2=Ostlie |first2=Dale A. |name-list-style= amp |title=An Introduction to Modern Stellar Astrophysics |publisher= Addison Wesley, San Francisco |date=2007 |isbn=978-0-8053-0348-3 }} 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.{{cite book|author=John Avison|title=The World of Physics|url=https://books.google.com/books?id=DojwZzKAvN8C&pg=PA397|date=November 2014|publisher=Nelson Thornes|isbn=978-0-17-438733-6|pages=397–}}

List of alpha nuclides

The entries for 36Ar and 40Ca are theoretical: they would release energy on decay, but the process has never been observed, and the half-lives are probably extremely long. Likewise, the chains for masses 64, 84, 92, and 96 theoretically can continue one more step by double electron capture (to 64Ni, 84Kr, 92Zr, and 96Mo respectively), but this has never been observed.

class="wikitable" style="margin:auto;"

!width="80"|Alpha number

!width="90"|nuclide

!width="150"|Stable/radioactive

!width="100"|decay mode

!width="100"|half-life{{NUBASE2016|ref}}

!width="160" |product(s) of decay (bold is stable)

!width="100"|alpha decay energy{{AME2020 II|ref}}

align="center"| 1

| align="center"| {{nuclide|link=yes|helium|4}}

| align="center"| Stable

| align="center"|

| align="center"|

| align="center"|

| align="center"|

align="center"| 2

| align="center"| {{nuclide|link=yes|beryllium|8}}

| align="center"| Radioactive

| align="center"| α

| align="center"| 8.19(37)×10−17 s

| align="center"| {{nuclide|link=yes|helium|4}}

| align="center"| +0.09184MeV

align="center"| 3

| align="center"| {{nuclide|link=yes|carbon|12}}

| align="center"| Stable

| align="center"|

| align="center"|

| align="center"|

| align="center"| -7.36659MeV

align="center"| 4

| align="center"| {{nuclide|link=yes|oxygen|16}}

| align="center"| Stable

| align="center"|

| align="center"|

| align="center"|

| align="center"| -7.16192MeV

align="center"| 5

| align="center"| {{nuclide|link=yes|neon|20}}

| align="center"| Stable

| align="center"|

| align="center"|

| align="center"|

| align="center"| -4.72985MeV

align="center"| 6

| align="center"| {{nuclide|link=yes|magnesium|24}}

| align="center"| Stable

| align="center"|

| align="center"|

| align="center"|

| align="center"| -9.31656MeV

align="center"| 7

| align="center"| {{nuclide|link=yes|silicon|28}}

| align="center"| Stable

| align="center"|

| align="center"|

| align="center"|

| align="center"| -9.98414MeV

align="center"| 8

| align="center"| {{nuclide|link=yes|sulfur|32}}

| align="center"| Stable

| align="center"|

| align="center"|

| align="center"|

| align="center"| -6.94766MeV

align="center"| 9

| align="center"| {{nuclide|link=yes|argon|36}}

| align="center"| Observationally Stable

| align="center"| (ECEC)

| align="center"| never seen

| align="center"| ({{nuclide|link=yes|sulfur|36}})

| align="center"| -6.64092MeV

align="center"| 10

| align="center"| {{nuclide|link=yes|calcium|40}}

| align="center"| Observationally Stable

| align="center"| (ECEC)

| align="center"| never seen

| align="center"| ({{nuclide|link=yes|argon|40}})

| align="center"| -7.03978MeV

align="center"| 11

| align="center"| {{nuclide|link=yes|titanium|44}}

| align="center"| Radioactive

| align="center"| EC

| align="center"| 60.0(11) y

| align="center"| {{nuclide|link=yes|scandium|44}} → {{nuclide|link=yes|calcium|44}}

| align="center"| -5.1271MeV

align="center"| 12

| align="center"| {{nuclide|link=yes|chromium|48}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 21.56(3) h

| align="center"| {{nuclide|link=yes|vanadium|48}} → {{nuclide|link=yes|titanium|48}}

| align="center"| -7.698MeV

align="center"| 13

| align="center"| {{nuclide|link=yes|iron|52}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 8.275(8) h

| align="center"| {{nuclide|link=yes|manganese|52|m}} → {{nuclide|link=yes|chromium|52}}

| align="center"| -7.936MeV

align="center"| 14

| align="center"| {{nuclide|link=yes|nickel|56}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 6.075(10) d

| align="center"| {{nuclide|link=yes|cobalt|56}} → {{nuclide|link=yes|iron|56}}

| align="center"| -8.0005MeV

align="center"| 15

| align="center"| {{nuclide|link=yes|zinc|60}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 2.38(5) min

| align="center"| {{nuclide|link=yes|copper|60}} → {{nuclide|link=yes|nickel|60}}

| align="center"| -2.6917MeV

align="center"| 16

| align="center"| {{nuclide|link=yes|germanium|64}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 63.7(25) s

| align="center"| {{nuclide|link=yes|gallium|64}} → {{nuclide|link=yes|zinc|64}}

| align="center"| -2.566MeV

align="center"| 17

| align="center"| {{nuclide|link=yes|selenium|68}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 35.5(7) s

| align="center"| {{nuclide|link=yes|arsenic|68}} → ... → {{nuclide|link=yes|zinc|68}}

| align="center"| -2.299MeV

align="center"| 18

| align="center"| {{nuclide|link=yes|krypton|72}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 17.16(18) s

| align="center"| {{nuclide|link=yes|bromine|72}} → ... → {{nuclide|link=yes|germanium|72}}

| align="center"| -2.176MeV

align="center"| 19

| align="center"| {{nuclide|link=yes|strontium|76}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 7.89(7) s

| align="center"| {{nuclide|link=yes|rubidium|76}} → ... → {{nuclide|link=yes|selenium|76}}

| align="center"| -2.73MeV

align="center"| 20

| align="center"| {{nuclide|link=yes|zirconium|80}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 4.6(6) s

| align="center"| {{nuclide|link=yes|yttrium|80}} → ... → {{nuclide|link=yes|krypton|80}}

| align="center"| -3.70MeV

align="center"| 21

| align="center"| {{nuclide|link=yes|molybdenum|84}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 3.8(9) ms

| align="center"| {{nuclide|link=yes|niobium|84}} → ... → {{nuclide|link=yes|strontium|84}}

| align="center"| -2.71MeV

align="center"| 22

| align="center"| {{nuclide|link=yes|ruthenium|88}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 1.3(3) s

| align="center"| {{nuclide|link=yes|technetium|88}} → ... → {{nuclide|link=yes|strontium|88}}

| align="center"| -2.27MeV

align="center"| 23

| align="center"| {{nuclide|link=yes|palladium|92}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 1.1(3) s

| align="center"| {{nuclide|link=yes|rhodium|92}} → ... → {{nuclide|link=yes|molybdenum|92}}

| align="center"| -2.28MeV

align="center"| 24

| align="center"| {{nuclide|link=yes|cadmium|96}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 1.003(47) s

| align="center"| {{nuclide|link=yes|silver|96}} → ... → {{nuclide|link=yes|ruthenium|96}}

| align="center"| -3.03MeV

align="center"| 25

| align="center"| {{nuclide|link=yes|tin|100}}

| align="center"| Radioactive

| align="center"| β+

| align="center"| 1.1(4) s

| align="center"| {{nuclide|link=yes|indium|100}} → ... → {{nuclide|link=yes|ruthenium|100}}

| align="center"| -3.47MeV

align="center"| 26

| align="center"| {{nuclide|link=yes|tellurium|104}}

| align="center"| Radioactive

| align="center"| α

| align="center"| <18 ns

| align="center"| {{nuclide|link=yes|tin|100}} → ... → {{nuclide|link=yes|ruthenium|100}}

| align="center"| +5.10MeV

align="center"| 27

| align="center"| {{nuclide|link=yes|xenon|108}}

| align="center"| Radioactive

| align="center"| α

| align="center"| 58{{su|p=+106|b=−23}} μs

| align="center"| {{nuclide|link=yes|tellurium|104}} → {{nuclide|link=yes|tin|100}} → ... → {{nuclide|link=yes|ruthenium|100}}

| align="center"| +4.57MeV

{{as of|2024}}, the heaviest known alpha nuclide is xenon-108.{{cite journal |last=Auranen |first=K. |display-authors=etal |date=2018 |title=Superallowed α decay to doubly magic 100Sn |journal=Physical Review Letters |volume=121 |issue=18 |pages=182501 |doi=10.1103/PhysRevLett.121.182501 |pmid=30444390 |url=https://www.pure.ed.ac.uk/ws/files/77942573/PhysRevLett.121.pdf |doi-access=free }}

References