What type of electron interaction occurs at the maximum probability of photoelectric absorption?

The maximum probability of photoelectric absorption occurs specifically during a photoelectric interaction. In this process, a photon completely transfers its energy to an inner-shell electron of an atom, resulting in the absorption of the photon and the ejection of that electron from the atom. The likelihood of such an event increases significantly when the photon energy is comparable to the binding energy of the electron, which is characteristic of the photoelectric effect.

This interaction is particularly significant in low-energy photon interactions (such as with X-rays or gamma rays) and is prominent in dense materials, such as bone or heavy metals, where the atomic number is high. The photoelectric effect is crucial for understanding how radiation interacts with matter, especially in medical applications like radiology and radiation therapy.

The other types of interactions mentioned, such as Compton scattering and elastic scattering, while also relevant in the context of photon interactions with matter, do not occur at the maximum probability of photoelectric absorption. Compton scattering involves the partial transfer of energy from a photon to an electron, and elastic scattering refers to interactions where energy is conserved, but the energy states of the interacting particles do not change. These are distinct processes that occur under different conditions compared to the photoelectric effect.