|San José State University|
& Tornado Alley
in Nuclei from Changes in the Number of Protons
These is considerable evidence that at least some of the neutrons and protons in a nucleus form alpha particles. A relatively large amount of energy is involved in the formation of an alpha particle, about 28.3 million electron volts (MeV). If a nuclide consists entirely of alpha particles then the removal of one of the constituents of an alpha particles should result in a relatively large effect on binding energy.
There are twenty five nuclides which could consist entirely of alpha particles. They will be referred to as alpha nuclides. The removal of a neutron from each of the alpha nuclide should result in a relatively large decrease in binding energy compared to that resulting from the addition of one neutron to each of the alpha nuclides. The evidence supports this proposition for the smaller nuclides.
The material below tests the proposition using data on the effect on binding energy of the subtraction of one proton from each alpha nuclide in comparison with the effect of adding one proton to such nuclides. kc
Due to One
Due to One
of an Alpha
Because the results for the subtraction and addition of protons are irregular and a bit puzzling the following graph on the incremental binding energies of alpha particles is presented first to show that regularities exist.
Here is the graph of the effect of removing one proton from each of the alpha nuclides.
Again shell phenomena is evidenced by the relatively sharp drop at the nuclear magic numbers of 6, 20 and 28.
The effect of adding one proton is much different from that for subtracting one proton.
Now the two previous graphs can be combined to show a comparison.
The two curves appear to be becoming approximately parallel. The more precise nature of the difference is shown below.l
This is remarkably similar to the corresponding graph for neutrons, as can be seen in the graph below.
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