Spheres · resonances
σ(ε) = (q + ε)² / (1 + ε²), with ε = 2(E − E₀)/Γ and the asymmetry parameter q (large q: a symmetric peak; q = 0: a dip). The calculator fits it to each feature of an exact spectrum. See Fano resonances explained.
An asymmetric line shape that appears when a narrow resonance interferes with a broad one, for example a quadrupole or a whispering-gallery mode on top of a broad dipole background.
The exact spectrum of a sphere or shell, a fit of each Fano feature (q parameter, width, position), the multipole contributions and a sensing figure of merit.
Fano line shapes of spheres and shells: exact spectra, fits and multipoles, in one click.