quadrupole
/ˈkwɑːdrəˌpoʊl/
noun
- A distribution of electric charge or magnetic field that has two positive and two negative poles, or a similar arrangement in physics.
- In chemistry, a quadrupole mass spectrometer helps identify molecules.
- The quadrupole magnet is used to focus particle beams in accelerators.
- The electric quadrupole moment of the nucleus affects its interaction with external fields.