## resonance fluorescence

https://doi.org/10.1351/goldbook.R05335
@F02453@ from the primary excited atomic or molecular species at the @W06659@ of the exciting radiation (no @R05285@ within the excited manifold). This term is also used to designate the radiation emitted by an atom of the same @W06659@ as the longest one capable of exciting its @F02453@, e.g. $$122.6\ \text{nm}$$ in the case of the hydrogen atom, and $$253.7\ \text{nm}$$ in the case of the mercury atom.