Editing Nuclear reaction (section)

== Nuclear reaction equations ==

Nuclear reactions may be shown in a form similar to chemical equations, for which [[invariant mass]] must balance for each side of the equation, and in which transformations of particles must follow certain conservation laws, such as conservation of charge and baryon number (total atomic [[mass number]]). An example of this notation follows:

{{block indent|[[Lithium-6|{{nuclide|lithium|6}}]]&nbsp;+&nbsp;[[Hydrogen-2|{{nuclide|hydrogen|2}}]]&nbsp;→&nbsp;[[Helium|{{nuclide|helium|4}}]]&nbsp;+&nbsp;?.}}

To balance the equation above for mass, charge and mass number, the second nucleus to the right must have atomic number 2 and mass number 4; it is therefore also helium-4. The complete equation therefore reads:

{{block indent|[[Lithium-6|{{nuclide|lithium|6}}]]&nbsp;+&nbsp;[[Hydrogen-2|{{nuclide|hydrogen|2}}]]&nbsp;→&nbsp;[[Helium|{{nuclide|helium|4}}]]&nbsp;+&nbsp;[[Helium|{{nuclide|helium|4}}]].}}

or more simply:

{{block indent|[[Lithium-6|{{nuclide|lithium|6}}]]&nbsp;+&nbsp;[[Hydrogen-2|{{nuclide|hydrogen|2}}]]&nbsp;→&nbsp;2&nbsp;[[Helium|{{nuclide|helium|4}}]].}}

Instead of using the full equations in the style above, in many situations a compact notation is used to describe nuclear reactions. This style of the form A(b,c)D is equivalent to A + b producing c + D. Common light particles are often abbreviated in this shorthand, typically p for proton, n for neutron, d for [[deuteron]], α representing an [[alpha particle]] or [[helium-4]], β for [[beta particle]] or electron, γ for [[gamma photon]], etc. The reaction above would be written as <sup>6</sup>Li(d,α)α.<ref>[http://www.astrophysicsspectator.com/topics/stars/FusionHydrogenRate.html The Astrophysics Spectator: Hydrogen Fusion Rates in Stars]</ref><ref>
{{cite book
|last=Tilley |first=R. J. D.
|year=2004
|title=Understanding Solids: The Science of Materials
|url=https://books.google.com/books?id=ZVgOLCXNoMoC&pg=PA495
|page=495
|publisher=[[John Wiley and Sons]]
|isbn=0-470-85275-5
}}</ref>