keVMeV

KeVMeV is not a single unit but a reference to energy scales in physics and related fields, specifically kiloelectronvolts (keV) and megaelectronvolts (MeV). The electronvolt is the amount of energy gained by an electron when it is accelerated by one volt; 1 eV equals 1.602176634×10−19 joules, so 1 keV equals 1.602176634×10−16 J and 1 MeV equals 1.602176634×10−13 J.

In practice, keV energies characterize X-ray photons from X-ray tubes and many astrophysical X-ray sources, while MeV energies characterize gamma rays from radioactive decay, nuclear transitions, and high-energy particle interactions. The keV–MeV range spans the typical operating energies of many detectors and imaging modalities. For example, diagnostic X-ray radiography and CT often use photons in the tens of keV to a few hundred keV; positron emission tomography emits 511 keV photons; gamma-ray spectroscopy commonly studies lines in the keV to MeV region.

Detectors are designed and calibrated for these energies; semiconductor devices such as germanium or cadmium zinc telluride operate with good energy resolution in the keV–MeV range, while scintillators like NaI(Tl) or BGO cover broader ranges. Spectral features include photopeaks and Compton continua that arise from keV–MeV interactions such as the photoelectric effect, Compton scattering, and, at higher energies, pair production.

KeVMeV thus serves as a shorthand for phenomena and instrumentation that function within these energy scales, distinguishing them from higher-energy regimes described in GeV or TeV used in high-energy particle physics.