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a discrete particle (quantum) of radiant energy.
pho·ton (hν, γ),(fō'ton),
In physics, a corpuscle of energy or particle of light; a quantum of light or other electromagnetic radiation.
photon/pho·ton/ (fo´ton) a particle (quantum) of radiant energy.
The elementary particle of light and other electromagnetic radiation; the quantum of electromagnetic energy. The photon is the massless, neutral vector boson that mediates electromagnetic interactions.
Etymology: Gk, phos, light
the smallest quantity of electromagnetic energy. It has no mass and no charge but travels at the speed of light. Photons may occur in the form of x-rays, gamma rays, or quanta of light. The energy (E) of a photon is expressed as the product of its frequency (v) and Planck's constant (h), as in the equation E = hv. X-ray photons occur in frequencies of 1018 to 1021 Hz and energies that range upward from 1 KeV.
physics A corpuscle of energy or particle of light; a quantum of light or other electromagnetic radiation.
photona quantum of radiant energy with a wavelength in the visible range of the ELECTROMAGNETIC SPECTRUM.
A light particle.
Mentioned in: Positron Emission Tomography (PET)
The basic unit of radiant energy defined by the equation
E = hνwhere h is Planck's constant (6.62 ✕ 10−34 joule ✕ second), ν the frequency of the light and E the energy difference carried away by the emission of a single photon of light. The term photon usually refers to visible light whereas the term quantum refers to other electromagnetic radiations. See quantum theory; wave theory; troland.
In physics, corpuscle of energy or particle of light; a quantum of light or other electromagnetic radiation.
n a bullet or quantum of electromagnetic radiant energy emitted and propagated from various types of radiation sources. The term should not be used alone but should be qualified by terms that will clarify the type of energy (e.g., light photon, radiographic photon).
a particle (quantum) of radiant energy.
a particle of x-ray energy.