Positron

Definition

A positron is the antiparticle of the electron, with the same mass but a positive charge. It plays a significant role in certain types of nuclear decay.

5 Must Know Facts For Your Next Test

1. Positrons are produced in beta-plus ($\beta^+$) decay, where a proton transforms into a neutron.
2. When a positron encounters an electron, they annihilate each other, producing gamma rays.
3. Positrons are used in medical imaging techniques such as Positron Emission Tomography (PET).
4. The existence of positrons was first predicted by Paul Dirac and later confirmed experimentally by Carl Anderson in 1932.
5. Positron emission is a process that helps to achieve stability in proton-rich nuclei.

Review Questions

• What happens when a positron collides with an electron?
• In which type of nuclear decay are positrons emitted?
• Who experimentally confirmed the existence of the positron?

Related terms

Beta-plus Decay: A type of radioactive decay where a proton is converted into a neutron, releasing a positron and a neutrino.

Antiparticle: A subatomic particle having the same mass as another particle but opposite electric or magnetic properties.

Gamma Rays:

High-energy electromagnetic waves emitted from atomic nuclei during radioactive decay or annihilation events involving particles like positrons.