In a photoelectric interaction, what happens to the photon?

In a photoelectric interaction, the photon loses all of its energy upon interaction with an atom. This process occurs when a high-energy photon strikes an atom and is completely absorbed by an inner-shell electron. As a result of this absorption, the electron is ejected from the atom with kinetic energy equal to the energy of the incoming photon minus the binding energy that holds the electron in its shell.

Once the photon is absorbed, it is no longer present, which effectively means it has lost all of its energy. This interaction contributes significantly to radiation dose delivery in medical applications, particularly in the context of radiation therapy, where understanding photon interactions with tissue is crucial for treatment planning.