What process primarily creates the majority of photons in an X-ray beam?

The primary process responsible for generating the majority of photons in an X-ray beam is Bremmstrahlung interactions. This phenomenon occurs when high-energy electrons are decelerated or deflected by the electric field of atomic nuclei as they pass through the anode material in an X-ray tube. As the electrons change direction and lose energy during this interaction, they emit X-ray photons.

Bremmstrahlung, which means "braking radiation" in German, accounts for the largest portion of the X-ray spectrum produced in diagnostic imaging. The process is significant because it produces a continuous spectrum of X-ray photon energies, which is essential for various imaging techniques.

Other processes like the photoelectric effect and characteristic interactions also contribute to the X-ray beam, but they are not the primary sources of photon generation. The photoelectric effect involves the absorption of photons by tissue, while characteristic interactions occur when an electron transitions between energy levels within an atom, creating X-rays at specific, fixed energies. Thermionic emission refers to the emission of electrons from the cathode when heated, which is necessary for creating the electron stream but does not produce X-ray photons directly.

Understanding Bremmstrahlung interactions is fundamental in radiography as it highlights how most of the X-ray energy