Gamow Shape · Methodology

A normalized teaching curve, not a reaction rate

The lesson multiplies an illustrative Maxwellian energy factor by a Coulomb-barrier penetration factor, then normalizes the sampled curve to its own maximum.

It does not include an absolute cross section, S-factor, resonance structure, density, composition, confinement time, screening correction, radiation loss, or device geometry. It cannot produce rate, power, gain, or net energy.

Equation

Displayed shape

shape(E) ∝ exp[−E/(kT) − √(E_G/E)]

The lesson uses E_G = 22.589 MeV for p–¹¹B and shows the analytic stationary point E₀ = [E_G(kT)²/4]^(1/3).

Boundary semantics

No edge optimum

If the largest sampled value occurs at the displayed energy limit, the interface reports a boundary maximum. The energy range must be extended before the peak is interpreted. A plotted edge is never relabelled as an optimum.

Reproduction steps

  1. Record the energy-unit ion temperature and displayed energy maximum.
  2. Generate the declared energy grid and evaluate the log-shape expression.
  3. Subtract the largest log value before exponentiation to avoid overflow/underflow.
  4. Normalize to the maximum sampled value and locate the analytic stationary point independently.
  5. Record whether the sampled maximum lies at the display boundary.
  6. Hash the canonical run specification; export inputs, constants, method version, and result.

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