Which of the following is an ionization process?

The process of ionization occurs when an atom loses or gains an electron, resulting in the formation of an ion. All of the listed effects—photoelectric effect, Compton scatter, and pair production—are mechanisms by which ionization can take place.

In the photoelectric effect, a photon interacts with an electron in an atom and transfers its energy to the electron, leading to the electron being ejected from the atom. This process causes the atom to become ionized because it loses an electron.

Compton scattering involves the collision between a photon and a loosely bound outer electron in an atom. The photon transfers part of its energy to the electron, which is then ejected from the atom. This results in ionization of the atom, as it too loses an electron.

Pair production occurs when a photon with sufficient energy (generally exceeding 1.022 MeV) interacts with the electromagnetic field of a nucleus, leading to the production of an electron-positron pair. The interaction results in energy being transformed into mass, and since an existing photon creates new charged particles, it also contributes to ionization processes.

Since each of these processes leads to the ionization of atoms, it is accurate to state that all of them constitute mechanisms of ion