Synthetic fluorescence spectra stick plots on a logarithmic intensity scale with the strongest lines normalized to 1 for Ni I (top) and Fe I (bottom) spanning 190–600 nm. Line intensities were calculated for the observing conditions of C/1996 B2 Hyakutake, v _h = −36.7 km s⁻¹ and r _h = 1.02 au.