Which type of radiation is produced when incident electrons interact with inner-shell electrons in the target?

• A. Characteristic radiation
• B. Bremsstrahlung radiation
• C. Scatter radiation
• D. Discrete radiation

Answer: (A)

When an incident electron ejects an inner-shell electron and that vacancy is filled by an electron from a higher shell, a photon is emitted with an energy equal to the difference between the two shell binding energies. This produces photons at specific energies unique to the element, giving characteristic lines in the spectrum. That discrete, element-specific emission is what characterizes characteristic radiation.

In contrast, bremsstrahlung arises from the deceleration of high-speed electrons in the nucleus’s electric field and yields a continuous spectrum, not discrete lines. Scatter radiation refers to photons deflected by interactions like Compton scattering, not the atomic-shell transitions that produce fixed-energy photons. The term discrete radiation isn’t the standard designation for this process.