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Electronvolt (unit)

An electronvolt (eV) is defined as the energy required to accelerate a single electron at rest through an electron potential difference of 1 volt in a vacuum.

1 eV ≈ 1.603 x 10-19 J

Electronvolts are a more mathematically convenient method to describe the miniscule quantity of energy associated with photons in imaging physics.

The energy required in diagnostic X-rays fall within the range of kiloelectron volts (keV), whereas the energy required in radiotherapy is often in terms of megaelectron volts (meV).

Imaging technology

Article information

rID: 79798
Synonyms or Alternate Spellings:
  • Electron volt

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