Electronvolt (unit)
Citation, DOI, disclosures and article data
Citation:
Vajuhudeen Z, Campos A, Chieng R, et al. Electronvolt (unit). Reference article, Radiopaedia.org (Accessed on 22 Mar 2025) https://doi.org/10.53347/rID-79798
rID:
79798
Article created:
5 Jul 2020,
Zemar Vajuhudeen
Disclosures:
At the time the article was created Zemar Vajuhudeen had no recorded disclosures.
View Zemar Vajuhudeen's current disclosures
Last revised:
Disclosures:
At the time the article was last revised Arlene Campos had no financial relationships to ineligible companies to disclose.
View Arlene Campos's current disclosures
Revisions:
9 times, by
6 contributors -
see full revision history and disclosures
Sections:
Synonyms:
- Megaelectronvolt (MeV)
- Kiloelectronvolt (keV)
- Electronvolt (eV)
- Gigaelectronvolt (GeV)
- Electron volt (eV)
- Kilo electronvolt (keV)
- Mega electronvolt (MeV)
- Giga electronvolt (GeV)
An electronvolt (eV) is defined as the energy required to accelerate a single electron at rest through an electron potential difference of one volt in a vacuum 3. This is different from the electrical potential difference applied to the X-ray tube in terms of kiloVolts (kV) 3. However, the kV applied to an X-ray tube is approximately equal to the maximum photon energy achievable by a photon (keVmax) 3.
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 falls within the range of kiloelectronvolts (keV), whereas the higher energy required in radiation therapy is often expressed in megaelectronvolts (MeV).
See also
References
- 1. Penelope J. Allisy-Roberts, Jerry Williams. Farr's Physics for Medical Imaging. (2007) ISBN: 9780702028441 - Google Books
- 2. Alan Martin, Sam Harbison, Karen Beach et al. An Introduction to Radiation Protection 6E. (2012) ISBN: 9781444146073 - Google Books
- 3. Penelope J. Allisy-Roberts, Jerry Williams. Farr's Physics for Medical Imaging. (2007) ISBN: 9780702028441 - Google Books
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