Binding Energy per Nucleon (Fusion vs Fission)

Trace the curve that explains where nuclear energy comes from — see why fusing light nuclei and splitting heavy ones both release energy, and check the energy of a specific reaction against the curve.

Still frame from the Binding Energy per Nucleon (Fusion vs Fission) simulation
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What you can adjust

Reaction
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Pick a reaction to check against the curve — fusing light nuclei (D+T), splitting a heavy one (U-235 fission), running the carbon-forming triple-alpha process backwards, or 'reacting' iron-56 with itself (no energy gain — it already sits at the curve's peak).

Highlight mass number (A)
1 – 240

Marks this mass number on the curve and reads off its binding energy per nucleon. Defaults to 56 (iron), right at the curve's peak.

Show measured reference points
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Plot real measured binding energies (AME2020) as reference dots alongside the formula curve — useful since the formula is known to under/over-shoot for very light nuclei.