Definition

Noun: A nuclear physics process in which a gamma-ray photon, interacting with the strong electric field near an atomic nucleus, is transformed into an electron and its antiparticle, a positron.

Usage

This term is used specifically in the context of particle physics, nuclear physics, and astrophysics to describe a fundamental process of matter creation. - Pair production is a key mechanism for the absorption of high-energy photons in matter. - The probability of pair production increases with the photon's energy. - Scientists observed the event through the signature of pair production in the detector.

Examples

• In a textbook: "For photons with energies exceeding 1.022 MeV, becomes the dominant interaction with matter."
• In a research paper: "The data confirms the theoretical cross-section for in the Coulomb field of a lead nucleus."
• In a lecture: "We can see from this cloud chamber photograph the distinct tracks resulting from ."

Advanced Usage

• "to undergo pair production": Describes the fate of a high-energy photon.
  • The gamma-ray photon from the cosmic event underwent pair production in the upper atmosphere.
• "pair production threshold": Refers to the minimum photon energy required for the process (twice the rest mass energy of an electron, or 1.022 MeV).
  • The experiment was designed to measure yields just above the pair production threshold.

Variants and Related Words

• Pair creation: A synonymous term often used interchangeably with .
• Annihilation: The inverse process to pair production, where a particle and its antiparticle (like an electron and positron) collide and are converted into energy, typically photons.

Synonyms

• Pair creation
• Materialization (in specific technical contexts)

Related Phrases and Concepts

• Breit-Wheeler process: Refers specifically to the collision of two photons to produce an electron-positron pair, a related but distinct process from the nuclear-field .
• Triplet production: A similar process where the photon interaction produces an electron-positron pair knocks out an atomic electron, resulting in three particles.

Noun

1. the transformation of a gamma-ray photon into an electron and a positron when the photon passes close to an atomic nucleus