Editing Openai/6897769e-4ee4-800f-aba5-69cca34f701c (section)

=== • For each wavelength λ I computed the primary-rainbow deviation angle D_min(λ) produced by a spherical water droplet (geometric optics ray-tracing: one internal reflection). ===
• I used an analytic toy dispersion n(λ) for liquid water (Cauchy-type: n(λ) = A + B/λ², λ in μm). This is an approximation (not high-precision refractive-index tables).
• I formed spectral weights:
* a Planck spectrum at T = 5800 K (Sun-like), and
* a “Planck + narrow emission lines” weighting (Hα, Hβ, Na D, OIII represented as narrow Gaussians). • I computed weighted means: ⟨D⟩ = ∫ D_min(λ) w(λ) dλ / ∫ w(λ) dλ and also evaluated single-line D_min values.

I ran everything numerically and plotted D_min(λ), the weights, and produced a small numerical table of results.