What would a chart of energy output of elements of mass X fused with hydrogen look like? What about X fused with X?

  • $\begingroup$ Are you asking about the energy released when you add one more proton to a particular nucleus? Did you try to find such a plot before asking here? You do realize that it depends on whether the resulting nuclide is stable - and that the answer will depend on both the # of protons and neutrons and therefore may be hard to represent in a "plot". How would you label the X axis? $\endgroup$ – Floris Jun 23 '15 at 13:58
  • $\begingroup$ @Floris yes i did search for it on google and other places, at no vail... I did not realized that the result might not be stable, but i guess that is irrelevant, even if the resulting atom only last a fraction of picosecond... and the X axis I would label as "Element of the Periodic Table" $\endgroup$ – Leonardo Jun 23 '15 at 14:22

See for example this table which contains the excess energy for each nuclide. You can take this table to compute the number you are interested in. The answer depends not only on the atomic number, but on the number of neutrons as well. This is why you need to think about how you want to represent this.

I recommend you study that table and then figure out how best to map it out. For example, if you take the entry for 3H, it shows an excess energy of 3.087994 MeV / nucleon; If you add a proton, it would turn into 4He, with an excess energy of 7.465077 MeV/nucleon. From this you can derive the energy released in the fusion to be

4*7.47 - 3*3.09 = 20.61 MeV

I was not able to verify this number - for most fusion reactions, the D+T reaction is used instead of H+T...

Doing this for every combination will take a bit of time and calculation... but this should get you going.

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  • $\begingroup$ Upon consideration, do you believe a 3D plot to be more meaningful, where the a axis is the number of protons another axis the "base" element and the other the amount of energy? The resulting plot would be a bunch of points I could color by initial element... $\endgroup$ – Leonardo Jun 23 '15 at 16:18
  • $\begingroup$ Yes - if you plot protons on one axis, neutrons on the other, and energy as the "color" in the third dimension, you might learn something. It will take some work to construct it... Uf you make a plot of excess energy for all isotopes you will already learn a lot. The plot you want is then the diff of this plot (what happens if you add one proton). Note most of these reactions could never take place... things might break up if you could give the proton enough energy to overcome the potential barrier. Fusion is complicated. $\endgroup$ – Floris Jun 23 '15 at 16:21

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