What is the term used to describe the interaction with matter involving the creation of a positron and an electron?

The interaction with matter involving the creation of a positron and an electron is called pair production. This phenomenon occurs when a photon with sufficient energy, typically above 1.022 MeV (the combined rest mass energy of a positron and an electron), interacts with a strong electromagnetic field, often near a nucleus, and produces a particle-antiparticle pair. In this case, the pair created consists of a positron, which is the antiparticle of the electron, and an electron itself.

Pair production is significant in high-energy physics and is a critical process in various applications, including particle physics and certain medical imaging techniques. It exemplifies how energy can be converted into mass, as described by Einstein's famous equation, E=mc².

The other interactions mentioned, such as the photoelectric effect, Compton scattering, and photodisintegration, involve different mechanisms and particles, highlighting the diverse ways that photons can interact with matter, but they do not produce particle-antiparticle pairs as pair production does.