Charles Barkla Created 2026-10-24 Updated 2026-11-05
Charles Barkla distinguished characteristic X-ray emission associated with a chemical element from radiation that varied more continuously with the exciting conditions. Comparisons of secondary radiation, absorption and emission showed that different chemical elements produce reproducible characteristic components. The emitting material therefore became an experimentally identifiable part of the spectrum. This work helped establish X-ray spectroscopy as a probe of atomic structure before a complete microscopic explanation of the characteristic lines was available.[ref][ref]